Monohydride and dihydride formation at Si(100) 2x1: A high resolution electron energy loss spectroscopy study
Abstract Results from EELS and LEED investigations on the interaction of atomic hydrogen with the Si(100) 2x1 surface give direct evidence for the formation of two distinct surface phases: a monohydride Si(100) 2x1:H and a dihydride Si(100) 1x1::2H phase. Temperature and exposure time determine which of the two phases appears. An analysis of normal vibrational modes leads to an identification of hydrogen adsorption complexes in both phases.
We present Monte Carlo simulation results for square-well homopolymers at a series of bond lengths. Although the model contains only isotropic pairwise interactions, under appropriate conditions this system shows spontaneous chiral symmetry breaking, where the chain exists in either a left- or a right-handed helical structure. We investigate how this behavior depends upon the ratio between bond length and monomer radius.