A structural model for hydrogenated amorphous silicon

A ball-and-stick model has been built to simulate the structure of hydrogenated amorphous silicon. The hydrogen content of the model, which incorporates 314 Si atoms, is approximately 20 atomic percent, and the density is in agreement with experiment. It is found that it is necessary to form local clusters of hydrogen atoms if no dangling bonds are to be left, but these are not of any simple recurrent type. The model contains only a few hydrogen atoms which are bonded in pairs to silicon atoms. Preliminary results are reported for the radial distribution functions, ring statistics and broadening of vibrational spectra of the model structure, and these are compared with recent experimental results. © 1980.