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arXiv · 0709.1451

Experimentally Constrained Molecular Relaxation: The case of hydrogenated amorphous silicon

Parthapratim Biswas·Raymond Atta-Fynn·David A. Drabold
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Abstract

We have extended our experimentally constrained molecular relaxation technique (P. Biswas {\it et al}, Phys. Rev. B {\bf 71} 54204 (2005)) to hydrogenated amorphous silicon: a 540-atom model with 7.4 % hydrogen and a 611-atom model with 22 % hydrogen were constructed. Starting from a random configuration, using physically relevant constraints, {\it ab initio} interactions and the experimental static structure factor, we construct realistic models of hydrogenated amorphous silicon. Our models confirm the presence of a high frequency localized band in the vibrational density of states due to Si-H vibration that has been observed in a recent vibrational transient grating measurements on plasma enhanced chemical vapor deposited films of hydrogenated amorphous silicon.

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Parthapratim Biswas, Raymond Atta-Fynn, David A. Drabold. 2007-09-10. Experimentally Constrained Molecular Relaxation: The case of hydrogenated amorphous silicon. https://doi.org/10.1103/physrevb.76.125210

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