electrostatic attraction between two oppositely charged dipoles is what type of bonding
Chemical bond


A chemical bond is a lasting attraction between atoms, ions or molecules that enables the formation of chemical compounds. The bond may result from the electrostatic force of attraction between oppositely charged ions as in ionic bonds or through the sharing of electrons as in covalent bonds. The strength of chemical bonds varies considerably; there are "strong bonds" or "primary bonds" such as covalent, ionic and metallic bonds, and "weak bonds" or "secondary bonds" such as dipole–dipole interactions, the London dispersion force and
6232641
Molecule


out of two or more elements. Covalent bond is a chemical bond that involves the sharing of electron pairs between atoms. These electron pairs are termed "shared pairs" or "bonding pairs", and the stable balance of attractive and repulsive forces between atoms, when they share electrons, is termed "covalent bonding". Ionic bonding is a type of chemical bond that involves the electrostatic attraction between oppositely charged ions, and is the primary interaction occurring in ionic compounds. The ions are atoms that have lost one or more
19776552
Ionic bonding


Ionic bonding is a type of chemical bonding that involves the electrostatic attraction between oppositely charged ions, and is the primary interaction occurring in ionic compounds. It is one of the main bonds along with Covalent bond and Metallic bonding. Ions are atoms that have gained one or more electrons (known as anions, which are negatively charged) and atoms that have lost one or more electrons (known as cations, which are positively charged). This transfer of electrons is known as electrovalence in contrast to covalence. In the simplest case
15052073
Chemical bond


ions, move independently through the solution, as do sodium ions, as Na. In water, charged ions move apart because each of them are more strongly attracted to a number of water molecules than to each other. The attraction between ions and water molecules in such solutions is due to a type of weak dipole-dipole type chemical bond. In melted ionic compounds, the ions continue to be attracted to each other, but not in any ordered or crystalline way. Covalent bonding is a common type of bonding in which
6232670
Lifshitz Theory of Van der Waals Force


two molecules, in this context, is the sum of the attractive or repulsive forces between them; these forces are primarily electrostatic in nature, and in their simplest form might consist of a force between two charges, two dipoles, or between a charge and a dipole. Thus, the strength of the force may often depend on the net charge, electric dipole moment, or the electric polarizability (formula_1) (see for example London force) of the molecules, with highly polarizable molecules contributing to stronger forces, and so
4560531
Microstructure


polymers (ionomers). Weak polar bonds are electrostatic and correspond to simple attractions between dipoles in compounds or molecules with inhomogeneous or polarizable charges. They act over long distances but with less intensity than strong bonds. Among them, for example, are van der Waals bonds between molecules and hydrogen bonds between water molecules in liquid water and ice. These bonds are found in all biological materials, certain hydrated minerals, polymers, and some mixed–composite materials. Weak nonpolar bonds or hydrophobic bonds are formed by repulsion. In a
16529259
Quantum-mechanical explanation of intermolecular interactions


In the natural sciences, an intermolecular force is an attraction between two molecules or atoms. They occur from either momentary interactions between molecules (the London dispersion force) or permanent electrostatic attractions between dipoles. They can be explained using a simple phenomenological approach (see intermolecular force), or using a quantum mechanical approach. Hydrogen bonding, dipole–dipole interactions, and London (Van der Waals) forces are most naturally accounted for by Rayleigh–Schrödinger perturbation theory (RS-PT). In this theory—applied to two
7631774
Molecular orbital


between the two atoms. The atoms are held together by the electrostatic attraction between the positively charged nuclei and the negatively charged electrons occupying bonding molecular orbitals. When atomic orbitals interact, the resulting molecular orbital can be of three types: bonding, antibonding, or nonbonding. Bonding MOs: Antibonding MOs: Nonbonding MOs: The type of interaction between atomic orbitals can be further categorized by the molecular-orbital symmetry labels σ (sigma), π (pi), δ (delta), φ (phi), γ (
19833984
Chemistry


Shell Electron Pair Repulsion model (VSEPR), and the concept of oxidation number can be used to explain molecular structure and composition. An ionic bond is formed when a metal loses one or more of its electrons, becoming a positively charged cation, and the electrons are then gained by the non-metal atom, becoming a negatively charged anion. The two oppositely charged ions attract one another, and the ionic bond is the electrostatic force of attraction between them. For example, sodium (Na), a metal, loses
4896872
Non-covalent interactions


). These include the following: Hydrogen bonding and halogen bonding are typically not classified as Van der Waals forces. Dipole-dipole interactions are electrostatic interactions between permanent dipoles in molecules. These interactions tend to align the molecules to increase attraction (reducing potential energy). Normally, dipoles are associated with electronegative atoms, including oxygen, nitrogen, sulfur, and fluorine. For example, acetone, the active ingredient in some nail polish removers, has a net dipole associated with the carbonyl (see figure 2). Since oxygen
19327783
Physical organic chemistry


, but are not limited to, hydrogen bonding, electrostatic interactions between charged molecules, dipole-dipole interactions, polar-π and cation-π interactions, π-stacking, donor-acceptor chemistry, and halogen bonding. In addition, the hydrophobic effect—the association of organic compounds in water—is an electrostatic, non-covalent interaction of interest to chemists. The precise physical origin of the hydrophobic effect originates from many complex interactions, but it is believed to be the most important component of biomolecular recognition in water
20668117
Intermolecular force


gases, but also to a universal force of attraction between macroscopic bodies. The first contribution to van der Waals forces is due to electrostatic interactions between charges (in molecular ions), dipoles (for polar molecules), quadrupoles (all molecules with symmetry lower than cubic), and permanent multipoles. It is termed the "Keesom interaction", named after Willem Hendrik Keesom. These forces originate from the attraction between permanent dipoles (dipolar molecules) and are temperature dependent. They consist of attractive interactions between dipoles that are ensemble
15518822
Intermolecular force


: Information on intermolecular forces is obtained by macroscopic measurements of properties like viscosity, pressure, volume, temperature (PVT) data. The link to microscopic aspects is given by virial coefficients and Lennard-Jones potentials. A "hydrogen bond" is the attraction between the lone pair of an electronegative atom and a hydrogen atom that is bonded to either nitrogen, oxygen, or fluorine. The hydrogen bond is often described as a strong electrostatic dipole–dipole interaction. However, it also has some features of covalent bonding: it
15518814
Metallic bonding


Metallic bonding is a type of chemical bonding that rises from the electrostatic attractive force between conduction electrons (in the form of an electron cloud of delocalized electrons) and positively charged metal ions. It may be described as the sharing of "free" electrons among a structure of positively charged ions (cations). Metallic bonding accounts for many physical properties of metals, such as strength, ductility, thermal and electrical resistivity and conductivity, opacity, and luster. Metallic bonding is not the only type of chemical bonding a metal can
20423242
Non-covalent interactions


by the positive charge of an alkali metal salt such as the sodium cation (Na). A hydrogen bond (H-bond), is a specific type of interaction that involves dipole-dipole attraction between a partially positive hydrogen atom and a highly electronegative, partially negative oxygen, nitrogen, sulfur, or fluorine atom (not covalently bound to said hydrogen atom). It is not a covalent bond, but instead is classified as a strong non-covalent interaction. It is responsible for why water is a liquid at
19327779
Electrostatic induction


while the positive nuclei are repelled and move slightly to the opposite side of the molecule. Since the negative charges are now closer to the external charge than the positive charges, their attraction is greater than the repulsion of the positive charges, resulting in a small net attraction of the molecule toward the charge. This is called polarization, and the polarized molecules are called dipoles. This effect is microscopic, but since there are so many molecules, it adds up to enough force to move a light object like Styrofoam. This is
14433161
Active site


a carboxylic acid (R-COOH) dissociates into RCOO and H ions, COO will attract positively charged groups such as protonated guanidine side chain of arginine. Hydrogen bond: A hydrogen bond is a specific type of dipole-dipole interaction between a partially positive hydrogen atom and a partially negative electron donor that contain a pair of electrons such as oxygen, sulfur and nitrogen. The strength of hydrogen bond depends on the chemical nature and geometric arrangement of each group. Van der Waals force: Van der Waals force is formed between
16423884
Chemical bond


that one atom may transfer an electron to the other. This transfer causes one atom to assume a net positive charge, and the other to assume a net negative charge. The "bond" then results from electrostatic attraction between atoms and the atoms become positive or negatively charged ions. Ionic bonds may be seen as extreme examples of polarization in covalent bonds. Often, such bonds have no particular orientation in space, since they result from equal electrostatic attraction of each ion to all ions around them. Ionic bonds are strong (
6232650
Triboelectric effect


a similarly electrified pen. This repulsion is readily detectable in the sensitive setup of hanging both pens on threads and setting them nearby one another. Such experiments readily lead to the theory of two types of quantifiable electric charge, one being effectively the negative of the other, with a simple sum respecting signs giving the total charge. The electrostatic attraction of the charged plastic pen to neutral uncharged pieces of paper (for example) is due to temporary charge separation (electric polarisation or dipole moment) of electric charges within the paper (
15264609
Chemical compound


. The metals in ionic bonding usually lose their valence electrons, becoming a positively charged cation. The nonmetal will gain the electrons from the metal, making the nonmetal a negatively charged anion. As outlined, ionic bonds occur between an electron donor, usually a metal, and an electron acceptor, which tends to be a nonmetal. Hydrogen bonding occurs when a hydrogen atom bonded to an electronegative atom forms an electrostatic connection with another electronegative atom through interacting dipoles or charges. A compound can be converted to a different chemical composition by
8932402
Docking theory of olfaction


The docking theory of olfaction proposes that the smell of an odorant molecule is due to a range of weak non-covalent interactions between the odorant [a ligand] and its protein odorant receptor (found in the nasal epithelium), such as electrostatic and Van der Waals interactions as well as H-bonding, dipole attraction, pi-stacking, metal ion, cation-pi interaction, and hydrophobic effects, in addition to odorant conformation. While this type of recognition has previously been termed the shape theory of olfaction, which
9103907
Chemical bond


. Strong chemical bonds are the "intramolecular" forces that hold atoms together in molecules. A strong chemical bond is formed from the transfer or sharing of electrons between atomic centers and relies on the electrostatic attraction between the protons in nuclei and the electrons in the orbitals. The types of strong bond differ due to the difference in electronegativity of the constituent elements. A large difference in electronegativity leads to more polar (ionic) character in the bond. Ionic bonding is a type of electrostatic interaction between atoms that have a large electronegativity
6232665
Electrostatic induction


if there was, it would attract opposite polarity charge to neutralize it. Therefore in induction, the mobile charges move under the influence of the external charge until they reach the surface of the metal and collect there, where they are constrained from moving by the boundary. This establishes the important principle that electrostatic charges on conductive objects reside on the surface of the object. External electric fields induce surface charges on metal objects that exactly cancel the field within. The electrostatic potential or voltage between two points is defined as the energy (
14433157
Electrostatic separator


remove foreign material to purify a substance. In mining, the process of crushing mining ore into particles for the purpose of separating minerals is called beneficiation. Generally, electrostatic charges are used to attract or repel differently charged material. When electrostatic separation uses the force of attraction to sort particles, conducting particles stick to an oppositely charged object, such as a metal drum, thereby separating them from the particle mixture. When this type of beneficiation uses repelling force, it is normally employed to change the trajectory of falling objects to sort
2469841
Electrostatic deflection (structural element)


when a material is brought into an electric field (E), the field tends to shift the positive charge (in red) and the negative charge (in blue) in opposite directions. Thus, induced dipoles are created. Fig. 3 shows a beam-like structure/element in an electric field. The interaction between the molecular dipole moment and the electric field results an induced torque (T). Then this torque tends to align the beam toward the direction of field. In case of a cantilevered CNT (
21786070
Non-covalent interactions


), or may be anionic, bearing a negative formal charge. As compared to hydrogen bonding, the halogen atom takes the place of the partially positively charged hydrogen as the electrophile. Halogen bonding should not be confused with halogen-aromatic interactions, as the two are related but differ by definition. Halogen-aromatic interactions involve an electron-rich aromatic π-cloud as a nucleophile; halogen bonding is restricted to monatomic nucleophiles. Van der Waals Forces are a subset of electrostatic interactions involving permanent or induced dipoles (or multipoles
19327782
Electret


then allowing it to re-solidify in a powerful electrostatic field. The polar molecules of the dielectric align themselves to the direction of the electrostatic field, producing a dipole electret with a permanent electrostatic 'bias'. Modern electrets are usually made by embedding excess charges into a highly insulating dielectric, e.g. by means of an electron beam, a corona discharge, injection from an electron gun, electric breakdown across a gap or a dielectric barrier, etc. There are two types of electrets: Cellular space charge electrets with internal bipolar
17122381
Alpha sheet


amyloid aggregation; the peptide bond has a relatively large intrinsic electrostatic dipole, but normally the dipoles of nearby bonds cancel each other out. In the alpha sheet, unlike other conformations, the peptide bonds are oriented in parallel so that the dipoles of the individual bonds can add up to create a strong overall electrostatic dipole. Notably, the protein lysozyme is among the few native-state proteins shown to contain an alpha-strand region; lysozyme from both chickens and humans contains an alpha strand located close to the site of a
6423278
Electrostatic deflection (molecular physics/nanotechnology)


E), the field tends to shift the positive charge (in red) and the negative charge (in blue) in opposite directions. Thus, induced dipoles are created. Fig. 3 shows a beam-like structure/element in an electric field. The interaction between the molecular dipole moment and the electric field results an induced torque (T). Then this torque tends to align the beam toward the direction of field. In case of a cantilevered CNT, it would be bent to the field direction. Meanwhile
21545824
Electric dipole moment


the right provides an intuitive idea of why a surface charge arises. The figure shows a uniform array of identical dipoles between two surfaces. Internally, the heads and tails of dipoles are adjacent and cancel. At the bounding surfaces, however, no cancellation occurs. Instead, on one surface the dipole heads create a positive surface charge, while at the opposite surface the dipole tails create a negative surface charge. These two opposite surface charges create a net electric field in a direction opposite to the direction of the dipoles. This
10814374
Non-covalent interactions


for all kind of donor-acceptor combinations. Halogen bonding is a type of non-covalent interaction which does not involve the formation nor breaking of actual bonds, but rather is similar to the dipole-dipole interaction known as hydrogen bonding. In halogen bonding, a halogen atom acts as an electrophile, or electron-seeking species, and forms a weak electrostatic interaction with a nucleophile, or electron-rich species. The nucleophilic agent in these interactions tends to be highly electronegative (such as oxygen, nitrogen, or sulfur
19327781
Dispersive adhesion


two molecules that have a permanent dipole due to electronegativity differences between atoms in the molecule. This dipole causes a coulombic attraction between the two molecules. Debye forces, or dipole-induced dipole interactions, can also play a role in dispersive adhesion. These come about when a nonpolar molecule becomes temporarily polarized due to interactions with a nearby polar molecule. This “induced dipole” in the nonpolar molecule then is attracted to the permanent dipole, yielding a Debye attraction. Sometimes grouped into the chemical mechanism of adhesion, hydrogen bonding can
16287395
Debye


The debye (symbol: D) (; ) is a CGS unit (a non-SI metric unit) of electric dipole moment named in honour of the physicist Peter J. W. Debye. It is defined as 1 statcoulomb-centimeters. Historically the debye was defined as the dipole moment resulting from two charges of opposite sign but an equal magnitude of 10 statcoulomb (generally called e.s.u. (electrostatic unit) in older literature), which were separated by 1 Ångström. This gave a convenient unit for molecular dipole moments. Typical
18161588
Non-covalent interactions


of the non-polar molecule to be polarized toward or away from the dipole (or "induce" a dipole) of the approaching molecule. Specifically, the dipole can cause electrostatic attraction or repulsion of the electrons from the non-polar molecule, depending on orientation of the incoming dipole. Atoms with larger atomic radii are considered more "polarizable" and therefore experience greater attraction as a result of the Debye force. London dispersion forces are the weakest type of non-covalent interaction. In organic molecules, however, the
19327786
Madelung constant


by electrostatics that the interaction between two point charges only accounts for the first term of a general Taylor series describing the interaction between two charge distributions of arbitrary shape. Accordingly, the Madelung constant only represents the monopole-monopole term. The electrostatic interaction model of ions in solids has thus been extended to a point multipole concept that also includes higher multipole moments like dipoles, quadrupoles etc. These concepts require the determination of higher order Madelung constants or so-called electrostatic lattice constants. In their case, instead of the nearest neighbor
1562720
Welding


to another atom to form oppositely charged ions. The bonding in the static position is when the ions occupy an equilibrium position where the resulting force between them is zero. When the ions are exerted in tension force, the inter-ionic spacing increases creating an electrostatic attractive force, while a repulsing force under compressive force between the atomic nuclei is dominant. Covalent bonding takes place when one of the constituent atoms loses one or more electrons, with the other atom gaining the electrons, resulting in an electron cloud that is shared by
1278837
Enone–alkene cycloadditions


-tail." Selectivity for one of these isomers depends on both steric and electronic factors (see below). The regiochemistry of the reaction is controlled primarily by two factors: steric interactions and electrostatic interactions between the excited enone and alkene. In their excited state, the polarity of enones is reversed so that the β carbon possesses a partial negative charge. In the transition state for the first bond formation, the alkene tends to align itself so that the negative end of its dipole points away from the β carbon of the
15440810
Heterogeneous catalysis


the adsorbent and the reactants are the adsorbate. Two types of adsorption are recognized: physisorption, weakly bound adsorption, and chemisorption, strongly bound adsorption. Many processes in heterogeneous catalysis lie between the two extremes. The Lennard-Jones model provides a basic framework for predicting molecular interactions as a function of atomic separation. In physisorption, a molecule becomes attracted to the surface atoms via van der Waals forces. These include dipole-dipole interactions, induced dipole interactions, and London dispersion forces. Note that no chemical bonds are formed
2595830
Electrostatic motor


An electrostatic motor or capacitor motor is a type of electric motor based on the attraction and repulsion of electric charge. An alternative type of electrostatic motor is the spacecraft electrostatic ion drive thruster where forces and motion are created by electrostatically accelerating ions. An electrostatic motor is based on the attraction and repulsion of electric charge. Usually, electrostatic motors are the dual of conventional coil-based motors. They typically require a high voltage power supply, although very small motors employ lower voltages. Conventional electric motors instead employ magnetic attraction and repulsion
18725235
Inductive effect


a permanent state of bond polarization, where the more electronegative atom has a fractional negative charge (δ–) and the less electronegative atom has a fractional positive charge (δ+). For example, the water molecule has an electronegative oxygen atom that attracts a negative charge. This is indicated by δ- in the water molecule in the vicinity of the O atom, as well as by a δ+ next to each of the two H atoms. The vector addition of the individual bond dipole moments results in a net dipole moment for
9235058
Chemical polarity


. Because the amount of charge separated in such dipoles is usually smaller than a fundamental charge, they are called partial charges, denoted as δ+ (delta plus) and δ− (delta minus). These symbols were introduced by Sir Christopher Ingold and Dr. Edith Hilda (Usherwood) Ingold in 1926. The bond dipole moment is calculated by multiplying the amount of charge separated and the distance between the charges. These dipoles within molecules can interact with dipoles in other molecules, creating dipole-dipole intermolecular forces. Bonds can fall between
4893015
Bond dipole moment


The bond dipole moment uses the idea of electric dipole moment to measure the polarity of a chemical bond within a molecule. It occurs whenever there is a separation of positive and negative charges. The bond dipole μ is given by: The bond dipole is modeled as +δ — δ- with a distance "d" between the partial charges +δ and δ-. It is a vector, parallel to the bond axis, pointing from minus to plus, as is conventional for electric dipole moment vectors. Chemists often draw the vector
10006812
Electrostatics


from contact with insulated surfaces. Coulomb's law states that: 'The magnitude of the electrostatic force of attraction or repulsion between two point charges is directly proportional to the product of the magnitudes of charges and inversely proportional to the square of the distance between them.' The force is along the straight line joining them. If the two charges have the same sign, the electrostatic force between them is repulsive; if they have different signs, the force between them is attractive. If formula_1 is the distance (in meters)
6954378
Ion association


and two cations. Higher aggregates, such as a tetramer (AB), may be formed. Ternary ion associates involve the association of three species. Another type, named "intrusion ion pair", has also been characterized. Ions of opposite charge are naturally attracted to each other by the electrostatic force. This is described by Coulomb's law: where "F" is the force of attraction, "q" and "q" are the magnitudes of the electrical charges, ε is the dielectric constant of the medium
16996477
Intermolecular force


values depend on the ionic strength I of the solution, as described by the Debye-Hückel equation, at zero ionic strength one observes G = 8 kJ/mol. Dipole–dipole interactions are electrostatic interactions between molecules which have permanent dipoles. These interactions tend to align the molecules to increase attraction (reducing potential energy). An example of a dipole–dipole interaction can be seen in hydrogen chloride (HCl): the positive end of a polar molecule will attract the negative end of the other molecule and influence its
15518818
Electrostatic fluid accelerator


in electrostatic fluid acceleration. Once the ions are created they have to be used to generate a thrust. This process relies on the same electrodes and electric field as the corona process. The ions that have been created have a net charge. Because of this charge they will be repelled from the electrode having the same charge and simultaneously attracted to the other electrode with the opposite charge. However, in between these electrodes are enormous numbers of neutral air molecules that have been unaffected by the ionization process. To reach the attracting electrode
11230339
Chemical compound


attractive forces that form when the electrons in two adjacent atoms are positioned so that they create a temporary dipole. Additionally, London dispersion forces are responsible for condensing non polar substances to liquids, and to further freeze to a solid state dependent on how low the temperature of the environment is. A covalent bond, also known as a molecular bond, involves the sharing of electrons between two atoms. Primarily, this type of bond occurs between elements that fall close to each other on the periodic table of elements, yet it is
8932400
Lone pair


atom and a smaller net positive charge on the hydrogen atoms. There is also a dipole associated with the lone pair and this reinforces the contribution made by the polar covalent N-H bonds to ammonia's dipole moment. In contrast to NH, NF has a much lower dipole moment of 0.24 D. Fluorine is more electronegative than nitrogen and the polarity of the N-F bonds is opposite to that of the N-H bonds in ammonia, so that the dipole due to the lone pair opposes the N-F bond
9862094
Chemical bond


hydrogen bonding. Since opposite charges attract via a simple electromagnetic force, the negatively charged electrons that are orbiting the nucleus and the positively charged protons in the nucleus attract each other. An electron positioned between two nuclei will be attracted to both of them, and the nuclei will be attracted toward electrons in this position. This attraction constitutes the chemical bond. Due to the matter wave nature of electrons and their smaller mass, they must occupy a much larger amount of volume compared with the nuclei, and this volume occupied by the
6232642
Electronic effect


"bond" and an electrostatic interaction. While an attractive electrostatic interaction is considered a "bond" if it gets too strong, a repulsive electrostatic interaction is always an electrostatic effect regardless of strength. An example of a repulsive effect is a molecule contorting to minimize the coulombic interactions of atoms that hold like charges. Electronic spin state at it simplest describes the number of unpaired electrons in a molecule. Most molecules including the proteins, carbohydrates, and lipids that make up the majority of life have no unpaired electrons even when charged
8159264
Cation–pi interaction


a cation–π interaction. Several criteria influence the strength of the bonding: the nature of the cation, solvation effects, the nature of the π system, and the geometry of the interaction. From electrostatics (Coulomb's law), smaller and more positively charged cations lead to larger electrostatic attraction. Since cation–π interactions are predicted by electrostatics, it follows that cations with larger charge density interact more strongly with π systems. The following table shows a series of Gibbs free energy of binding between benzene and several cations
1244898
Self-healing hydrogels


microstructure, hydrogels are not homogenous within the selected solvent system. The following sections summarize the chemical and physical methods by which hydrogels are crosslinked. Hydrogen bonding is a strong intermolecular force that forms a special type of dipole-dipole attraction. Hydrogen bonds form when a hydrogen atom bonded to a strongly electronegative atom is around another electronegative atom with a lone pair of electrons. Hydrogen bonds are stronger than normal dipole-dipole interactions and dispersion forces but they remain weaker than covalent and ionic bonds. In hydrogels, structure and stability of
7223752
Chemical bond


charge. Such bonds occur between two atoms with moderately different electronegativities and give rise to dipole–dipole interactions. The electronegativity difference between the two atoms in these bonds is 0.3 to 1.7. A single bond between two atoms corresponds to the sharing of one pair of electrons. The Hydrogen (H) atom has one valence electron. Two Hydrogen atoms can then form a molecule, held together by the shared pair of electrons. Each H atom now has the noble gas electron configuration of helium (He). The pair of
6232673
Electric charge


of an electron is negative, "−e", while that of a proton is positive, "+e". Charged particles whose charges have the same sign repel one another, and particles whose charges have different signs attract. Coulomb's law quantifies the electrostatic force between two particles by asserting that the force is proportional to the product of their charges, and inversely proportional to the square of the distance between them. The charge of an antiparticle equals that of the corresponding particle, but with opposite sign. The electric charge
9683248
Hamiltonian (quantum mechanics)


a configuration of discrete point charges): where formula_70 is the electrostatic potential of charge formula_68 at formula_72. The total potential of the system is then the sum over formula_73: so the Hamiltonian is: For an electric dipole moment formula_76 constituting charges of magnitude formula_35, in a uniform, electrostatic field (time-independent) formula_78, positioned in one place, the potential is: the dipole moment itself is the operator Since the particle is stationary, there is no translational kinetic energy of the dipole, so the Hamiltonian of the
14644594
Gas


, Joseph Gay-Lussac and Amedeo Avogadro for a variety of gases in various settings. Their detailed studies ultimately led to a mathematical relationship among these properties expressed by the ideal gas law (see simplified models section below). Gas particles are widely separated from one another, and consequently, have weaker intermolecular bonds than liquids or solids. These intermolecular forces result from electrostatic interactions between gas particles. Like-charged areas of different gas particles repel, while oppositely charged regions of different gas particles attract one another; gases that contain
850143
Electronic effect


. This is simple one example of many varied examples, including aspects of pericyclic reactions such as the Diels-Alder reaction, among others. Electrostatic interactions include both attractive and repulsive forces associated with the build-up of charge in a molecule. Electrostatic interactions are generally too weak to be considered traditional bonds or are prevented from forming a traditional bond, possibly by a steric effect. A bond is usually defined as two atoms approaching closer than the sum of their Van der Waal radii. Hydrogen bonding borders on being an actual
8159263
Chemical polarity


Polar molecules must contain polar bonds due to a difference in electronegativity between the bonded atoms. A polar molecule with two or more polar bonds must have a geometry which is asymmetric in at least one direction, so that the bond dipoles do not cancel each other. Polar molecules interact through dipole–dipole intermolecular forces and hydrogen bonds. Polarity underlies a number of physical properties including surface tension, solubility, and melting and boiling points. Not all atoms attract electrons with the same force. The amount of "pull" an atom
4893013
Optical tweezers


particle can be treated as a point dipole in an inhomogeneous electromagnetic field. The force applied on a single charge in an electromagnetic field is known as the Lorentz force, The force on the dipole can be calculated by substituting two terms for the electric field in the equation above, one for each charge. The polarization of a dipole is formula_2 where formula_3 is the distance between the two charges. For a point dipole, the distance is infinitesimal, formula_4 Taking into account that the two charges have opposite signs, the force takes
7325400
Hyperconjugation


by Fernández and Frenking (2006) summarized the trends in hyperconjugation among various groups of acyclic molecules, using energy decomposition analysis or EDA. Fernández and Frenking define this type of analysis as "...a method that uses only the pi orbitals of the interacting fragments in the geometry of the molecule for estimating pi interactions." For this type of analysis, the formation of bonds between various molecular moieties is a combination of three component terms. ΔE represents what Fernández and Frenking call a molecule’s “quasiclassical electrostatic attractions.” The
17120748
Dust collector


pass through the ionized field between the electrodes. These charged particles are then attracted to a grounded or positively charged electrode and adhere to it. The collected material on the electrodes is removed by rapping or vibrating the collecting electrodes either continuously or at a predetermined interval. Cleaning a precipitator can usually be done without interrupting the airflow. The four main components of all electrostatic precipitators are: The following factors affect the efficiency of electrostatic precipitators: There are two main types of precipitators: Described below is the high-voltage, single-
14262979
Transition dipole moment


, the two charges will experience a force in opposite directions, leading to a net torque on the dipole. The magnitude of the torque is proportional to both the magnitude of the charges and the separation between them, and varies with the relative angles of the field and the dipole: Similarly, the coupling between an electromagnetic wave and an atomic transition with transition dipole moment formula_22 depends on the charge distribution within the atom, the strength of the electric field, and the relative polarizations of the field and the transition. In addition
6787539
Relaxation (NMR)


physical system, but a simple approximation called the BPP theory is widely used. Another relaxation mechanism is the electrostatic interaction between a nucleus with an electric quadrupole moment and the electric field gradient that exists at the nuclear site due to surrounding charges. Thermal motion of a nucleus can result in fluctuating electrostatic interaction energies. These fluctuations produce transitions between the nuclear spin states in a similar manner to the magnetic dipole-dipole interaction. In 1948, Nicolaas Bloembergen, Edward Mills Purcell, and Robert Pound proposed the so-called Bloembergen-
11691304
Vibration theory of olfaction


The vibration theory of smell proposes that a molecule's smell character is due to its vibrational frequency in the infrared range. This controversial theory is an alternative to the more widely accepted docking theory of olfaction (formerly termed the shape theory of olfaction), which proposes that a molecule's smell character is due to a range of weak non-covalent interactions between its protein odorant receptor (found in the nasal epithelium), such as electrostatic and Van der Waals interactions as well as H-bonding, dipole attraction, pi-
9205649
Janus particles


dipolar (zwitterionic), micronsized Janus particles, whose two sides are both fully water-soluble. Zwitterionic Janus particles do not behave like classical dipoles, since their size is much larger than the distance at which electrostatic attractions are strongly felt. The study of zwitterionic Janus particles once again demonstrates their ability to form defined clusters. However, this particular type of Janus particle prefers to aggregate into larger clusters since this is more energetically favorable because each cluster carries a macroscopic dipole which allows the aggregation of already-formed clusters into larger
5679541
Work function


dependent on the "internal vacuum level" inside the material (i.e., its average electrostatic potential), because of the formation of an atomic-scale electric double layer at the surface. This surface electric dipole gives a jump in the electrostatic potential between the material and the vacuum. A variety of factors are responsible for the surface electric dipole. Even with a completely clean surface, the electrons can spread slightly into the vacuum, leaving behind a slightly positively charged layer of material. This primarily occurs in metals, where the
9242841
Magnepan


the Magneplanar. Martin-Logan and Quad Electroacoustics, among others, make electrostatic loudspeakers, which are another variation on the dipole model. Electrostatic speakers operate on a somewhat different principle. While the voice coils in the Magneplanar are conductive wires or foil strips mounted on a sheet of Mylar film, electrostatic speakers suspend a charged conductive film between two grids (stators) which move the film. One disadvantage of both designs is that a very large panel is required to produce deep bass. Magnepan has addressed this via the physical size
17585012
Dipole


For ozone (O) which is also a bent molecule, the bond dipole moments are not zero even though the O−O bonds are between similar atoms. This agrees with the Lewis structures for the resonance forms of ozone which show a positive charge on the central oxygen atom. An example in organic chemistry of the role of geometry in determining dipole moment is the "cis" and "trans" isomers of 1,2-dichloroethene. In the "cis" isomer the two polar C−Cl bonds are on the same side of the C=C
8378589
Bond valence method


plausible network can be created by connecting well matched cations and anions that satisfy Eq. 4. If the finite network contains only cation-anion bonds, every bond can be treated as an electric capacitor (two equal and opposite charges linked by electrostatic flux). The bond network is thus equivalent to a capacitive electrical circuit with the charge on each capacitor being equivalent to the bond valence. The individual bond capacitors are not initially known, but in the absence of any information to the contrary we assume that they are all equal
21896891
Earnshaw's theorem


theorem holds for a single point charge then it would also hold for two opposite point charges connected together. In particular, it would hold in the limit where the distance between the charges is decreased to zero while maintaining the dipole moment – that is, it would hold for an electric dipole. But if the theorem holds for an electric dipole, then it will also hold for a magnetic dipole, since the (static) force/energy equations take the same form for both electric and magnetic dipoles. As a practical consequence
15710754
Double layer (surface science)


liquid "ionic" conductor (electrolyte), a common boundary (interface) among the two phases appears. Hermann von Helmholtz was the first to realize that charged electrodes immersed in electrolyte solutions repel the co-ions of the charge while attracting counterions to their surfaces. Two layers of opposite polarity form at the interface between electrode and electrolyte. In 1853 he showed that an electrical double layer (DL) is essentially a molecular dielectric and stores charge electrostatically. Below the electrolyte's decomposition voltage, the stored charge is linearly dependent
15218551
Polymer


urethane or urea linkages. Polyesters have dipole-dipole bonding between the oxygen atoms in C=O groups and the hydrogen atoms in H-C groups. Dipole bonding is not as strong as hydrogen bonding, so a polyester's melting point and strength are lower than Kevlar's (Twaron), but polyesters have greater flexibility. Ethene, however, has no permanent dipole. The attractive forces between polyethylene chains arise from weak Van der Waals forces. Molecules can be thought of as being surrounded by a cloud of negative electrons
3215409
Electrostatic voltmeter


-surface distances. The technique also prevents arc-over between the probe and measured surface when measuring high voltages. The operating principle of an electrostatic voltmeter is similar to that of an electrometer, it is, however, designed to measure high potential differences; typically from a few hundred to many thousands volts. An electrostatic voltmeter uses the attraction force between two charged surfaces to create a deflection of a pointer directly calibrated in volts. Since the attraction force is the same regardless of the polarity of the charged surfaces (as long
15577685
Mineral processing


the isamill. Staged flotation reactors (SFRs) split the flotation process into 3 defined stages per cell and are becoming increasingly more common in use as they require much less energy, air and installation space. There are two main types of electrostatic separators. These work in similar ways, but the forces applied to the particles are different and these forces are gravity and electrostatic attraction. The two types are electrodynamic separators (or high tension rollers) or electrostatic separators. In high tension rollers, particles are charged by a corona discharge
10769035
Drug action


the drug can bind with amino groups on the receptor. This type of bond is very strong, and varies with the inverse of the distance between the atoms so that it can act over large distances. Cation-π interactions can also be classified as ionic bonding. This type of interaction occurs when a cation, e.g. acetylcholine, interacts with the negative π bonds on an aromatic group of the receptor. Ion-dipole and dipole-dipole bonds have similar interactions, but are more complicated and are weaker than ionic bonds.
4110583
Ionic compound


atoms can be ionized by electron transfer, a process thermodynamically understood using the Born–Haber cycle. Ions in ionic compounds are primarily held together by the electrostatic forces between the charge distribution of these bodies, and in particular the ionic bond resulting from the long-ranged Coulomb attraction between the net negative charge of the anions and net positive charge of the cations. There is also a small additional attractive force from van der Waals interactions which contributes only around 1–2% of the cohesive energy for small ions. When a pair of
911440
Hydrogen bond


covalently bound to the hydrogen is named the proton donor. In the donor molecule, the H center is protic. The donor is a Lewis base. Hydrogen bonds are represented as H···Y system, where the dots represent the hydrogen bond. Liquids that display hydrogen bonding (such as water) are called associated liquids. The hydrogen bond is often described as an electrostatic dipole-dipole interaction. However, it also has some features of covalent bonding: it is directional and strong, produces interatomic distances shorter than the sum of the
13330816
Storage ring


. A force must be applied to particles in such a way that they are constrained to move approximately in a circular path. This may be accomplished using either dipole electrostatic or dipole magnetic fields, but because most storage rings store relativistic charged particles it turns out that it is most practical to utilise magnetic fields produced by dipole magnets. However, electrostatic accelerators have been built to store very low energy particles, and quadrupole fields may be used to store (uncharged) neutrons; these are comparatively rare, however. Dipole magnets alone
15205667
Carbon–fluorine bond


iodine, respectively. The carbon–fluorine bond length is typically about 1.35 ångström (1.39 Å in fluoromethane). It is shorter than any other carbon–halogen bond, and shorter than single carbon–nitrogen and carbon–oxygen bonds, despite fluorine having a larger atomic mass. The short length of the bond can also be attributed to the ionic character/electrostatic attractions between the partial charges on carbon and fluorine. The carbon–fluorine bond length varies by several hundredths of an ångstrom depending on the hybridization of the carbon
2593085
Electric dipole moment


, and as in mechanics, it is computationally and theoretically useful to choose the center of mass as the observation point. For a charged molecule the center of charge should be the reference point instead of the center of mass. For neutral systems the references point is not important. The dipole moment is an intrinsic property of the system. An ideal dipole consists of two opposite charges with infinitesimal separation. The potential and field of such an ideal dipole are found next as a limiting case of an example of two opposite charges at
10814360
Anodic bonding


affects a positive volume charge in the silicon wafer on the opposite side. As a result a few micrometer thick high-impedance depletion region is developed at the bond barrier in the glass wafer. In the gap between silicon and glass the bond voltage drops. The bond process as a combination of electrostatic and electrochemical process starts. The electrical field intensity in the depletion region is so high that the oxygen ions drift to the bond interface and pass out to react with the silicon to form SiO (compare to figure "ion drifting
20048873
Dipole


double bond and the molecular dipole moment is 1.90 D. In the "trans" isomer, the dipole moment is zero because the two C−Cl bonds are on opposite sides of the C=C and cancel (and the two bond moments for the much less polar C−H bonds also cancel). Another example of the role of molecular geometry is boron trifluoride, which has three polar bonds with a difference in electronegativity greater than the traditionally cited threshold of 1.7 for ionic bonding. However, due to the equilateral triangular distribution of the fluoride
8378590
Charge density


materials, the total charge of an object can be separated into "free" and "bound" charges. Bound charges set up electric dipoles in response to an applied electric field E, and polarize other nearby dipoles tending to line them up, the net accumulation of charge from the orientation of the dipoles is the bound charge. They are called bound because they cannot be removed: in the dielectric material the charges are the electrons bound to the nuclei. Free charges are the excess charges which can move into electrostatic equilibrium
2238354
Force between magnets


where "q" is the 'magnetic charge'. The direction of the magnetic dipole moment points from the negative south pole to the positive north pole of this tiny magnet. Magnets are drawn along the magnetic field gradient. The simplest example of this is the attraction of opposite poles of two magnets. Every magnet produces a magnetic field that is stronger near its poles. If opposite poles of two separate magnets are facing each other, each of the magnets are drawn into the stronger magnetic field near the pole of the other
8654790
Dispersive adhesion


an individual basis, these attractions are not very strong, but when summed over the bulk of a material, can become significant. London dispersion forces arise from instantaneous dipoles between two nonpolar molecules close together. The random nature of electron orbit allows moments in which the charge distribution in a molecule is unevenly distributed, allowing an attraction to another molecule with a temporary dipole. A larger molecule allows for a larger dipole, and thus will have stronger dispersion forces. Keesom forces, also known as dipole-dipole interactions, result from
16287394
Neutron


neutron assists it to be attracted to the protons with which it interacts in the nucleus. (However, the main attraction between neutrons and protons is via the nuclear force, which does not involve electric charge.) The simplified classical view of the neutron's charge distribution also "explains" the fact that the neutron magnetic dipole points in the opposite direction from its spin angular momentum vector (as compared to the proton). This gives the neutron, in effect, a magnetic moment which resembles a negatively charged particle. This
1589261
Force between magnets


to the area in a direction determined using the current and the right-hand rule. As such, the SI unit of magnetic dipole moment is ampere meter. More precisely, to account for solenoids with many turns the unit of magnetic dipole moment is Ampere-turn meter. In the Gilbert model, the magnetic dipole moment is due to two equal and opposite magnetic charges that are separated by a distance, "d". In this model, m is similar to the electric dipole moment p due to electrical charges:
8654789
Kelvin water dropper


The Kelvin water dropper, invented by Scottish scientist William Thomson (Lord Kelvin) in 1867, is a type of electrostatic generator. Kelvin referred to the device as his water-dropping condenser. The apparatus is variously called the Kelvin hydroelectric generator, the Kelvin electrostatic generator, or Lord Kelvin's thunderstorm. The device uses falling water to generate voltage differences by electrostatic induction occurring between interconnected, oppositely charged systems. Its only use has been in physics education to demonstrate the principles of electrostatics. A typical setup is shown in Fig
9067434
Carbon–fluorine bond


most unreactive organic compounds. The high electronegativity of fluorine (4.0 for F vs. 2.5 for carbon) gives the carbon–fluorine bond a significant polarity/dipole moment. The electron density is concentrated around the fluorine, leaving the carbon relatively electron poor. This introduces ionic character to the bond through partial charges (C—F). The partial charges on the fluorine and carbon are attractive, contributing to the unusual bond strength of the carbon–fluorine bond. The bond is labeled as "the strongest in organic chemistry,
2593083
Intermolecular force


forces are discussed further in the section about the Keesom interaction, below. Ion–dipole and ion–induced dipole forces are similar to dipole–dipole and dipole–induced dipole interactions but involve ions, instead of only polar and non-polar molecules. Ion–dipole and ion–induced dipole forces are stronger than dipole–dipole interactions because the charge of any ion is much greater than the charge of a dipole moment. Ion–dipole bonding is stronger than hydrogen bonding. An ion–dipole force consists of an
15518820
Electric dipole moment


. For two opposite charges, denoting the location of the positive charge of the pair as r and the location of the negative charge as r : showing that the dipole moment vector is directed from the negative charge to the positive charge because the position vector of a point is directed outward from the origin to that point. The dipole moment is particularly useful in the context of an overall neutral system of charges, for example a pair of opposite charges, or a neutral conductor in a uniform electric field. For such a system
10814357
Polymer


its own chains. These stronger forces typically result in higher tensile strength and higher crystalline melting points. The intermolecular forces in polymers can be affected by dipoles in the monomer units. Polymers containing amide or carbonyl groups can form hydrogen bonds between adjacent chains; the partially positively charged hydrogen atoms in N-H groups of one chain are strongly attracted to the partially negatively charged oxygen atoms in C=O groups on another. These strong hydrogen bonds, for example, result in the high tensile strength and melting point of polymers containing
3215408
Steroid Delta-isomerase


. More specifically, Tyr-14 and Asp-99 dipoles work to stabilize the growing charge which accumulates on the enolate oxygen (O-3) throughout catalysis. In a similar way, the charge on Asp38 is stabilized by surrounding residues and a water molecule during the course of the reaction. The Boxer group used experimental Stark spectroscopy methods to identify the presence of H-bond-mediated electric fields within the KSI active site. These measurements quantified the electrostatic contribution to KSI catalysis (70%). The active site is lined with hydrophobic residues to
8482500
Hydrogen bond


, and the dotted or dashed line indicates the hydrogen bond. The use of three centered dots for the hydrogen bond is specifically recommended by the IUPAC. There is general agreement that there is actually a minor covalent component to hydrogen bonding, especially for moderate to strong hydrogen bonds ( 5 kcal/mol), although the importance of covalency in hydrogen bonding is debated. At the opposite end of the scale, there is no clear boundary between a weak hydrogen bond and a van der Waals (e.g., dipole-dipole)
13330809
Non-covalent interactions


different molecules, rather than between different atoms of the same molecule "For a more detailed introduction to electrostatics, see Coulomb's Law" Ionic interactions involve the attraction of ions or molecules with full permanent charges of opposite signs. For example, sodium fluoride involves the attraction of the positive charge on sodium (Na) with the negative charge on fluoride (F). However, this particular interaction is easily broken upon addition to water, or other highly polar solvents. In water ion pairing is mostly entropy driven; a single
19327777
Chemical bond


predict the strength, directionality, and polarity of bonds. The octet rule and VSEPR theory are two examples. More sophisticated theories are valence bond theory, which includes orbital hybridization and resonance, and molecular orbital theory which includes linear combination of atomic orbitals and ligand field theory. Electrostatics are used to describe bond polarities and the effects they have on chemical substances. A chemical bond is an attraction between atoms. This attraction may be seen as the result of different behaviors of the outermost or valence electrons of atoms. These behaviors merge
6232644
Triboelectric effect


the different molecules. While adhesion is not a chemical bond between atoms, there is an exchange of electrons between the different types of molecules, resulting in an electrostatic attraction between the molecules that holds them together. Physical separation of materials that are adhered together results in friction between the materials. Because the electron transfer between molecules in the different materials is not immediately reversible, the excess electrons in one type of molecule remain left behind, while a deficit of electrons occurs in the other. Thus, a material can develop a positive
15264611
Half-reaction


, redox reaction takes place, we do not see the electrons as they appear and disappear during the course of the reaction. What we see is the reactants (starting material) and end products. Due to this, electrons appearing on both sides of the equation are canceled. After canceling, the equation is re-written as Two ions, positive (Mg) and negative (O) exist on product side and they combine immediately to form a compound magnesium oxide (MgO) due to their opposite charges (electrostatic attraction
17628547
Bond valence method


valence method is a development of Pauling's rules. In 1930, Bragg showed that Pauling's electrostatic valence rule could be represented by electrostatic lines of force emanating from cations in proportion to the cation charge and ending on anions. The lines of force are divided equally between the bonds to the corners of the coordination polyhedron. Starting with Pauling in 1947 a correlation between cation–anion bond length and bond strength was noted. It was then shown later that if bond lengths were included in the calculation of bond strength, its accuracy
21896896
Electric dipole moment


Here, the electric dipole moment p is, as above: The result for the dipole potential also can be expressed as: which relates the dipole potential to that of a point charge. A key point is that the potential of the dipole falls off faster with distance "R" than that of the point charge. The electric field of the dipole is the negative gradient of the potential, leading to: Thus, although two closely spaced opposite charges are "not quite" an ideal electric dipole (because their potential at
10814362