Mass Spectrometric Study of Stability, Thermochemistry and Structures of the Gaseous Oxyacid Salts
Experimental data obtained by Knudsen Effusion Mass Spectrometry and results of quantum-chemical calculations on the structure and thermodynamic properties of gaseous oxyacid salts were systematized. A criterion of thermal stability of these compounds was offered and regularities in the atomization enthalpies were established.
Vapor pressures and thermodynamic properties of simple and complex iodides
Abstract The vapor composition above KI, FeI2, CdI2, KI-FeI2-Ag and KI-CdI2-Ag systems were studied by the Knudsen effusion mass spectrometry. Temperature dependences of partial pressures of gaseous species above pure iodides were determined. Equilibrium constants and reaction enthalpies of compounds with the participation of formed complex iodides were obtained. Structures, molecular parameters and thermodynamic functions of gaseous KCdI3, KFeI3 and KAgI2 were calculated by quantum chemistry methods. The obtained values of formation enthalpies (ΔfH0 (298.15) for gaseous complex iodides KCdI3, KFeI3 and KAgI2 are equal to −320.0±7.3 −218.0±6.6 and −174.5±12.0 kJ/mol, respectively.
Mass Spectrometric Study of Ions Formed from Cesium Metaborate Vapor under Electron Impact
An ionization behavior of cesium metaborate vapor under electron impact has been studied by a mass spectrometric method. Formations of Cs2+, CsB+, CsO+, Cs+ 2, Cs2O+, B+ and BO− 2 ions have been identified in addition to the well known ions of Cs+, CsBO+, CsBO+ 2 and Cs2BO+ 2. Ionization processes and vapor precursors for these ions have been given from ionization efficiency curves, appearance energies, temperature dependence of ion intensities and energetics of the ionization processes as follows: the process for the formations of Cs+ with AE(Cs+)=3.9± 1.0 eV and BO− 2 ions is the ion pair formation from CsBO2(g), that for CsBO+ 2 ion is the simple ionization of CsBO2(g), that for Cs+ with AE (Cs+) =9.1±0.5 eV, Cs2+, CsBO+, CsB+, CsO+ and B+ ions is the dissociative ionization from CsBO2(g) and that for Cs+ 2, Cs2O+ and Cs2BO+ 2 ions is the dissociative ionization from Cs2(BO2)2(g). The knowledge of the ionization behavior of cesium metaborate vapor under electron impact is very useful in the mass spectr...