CLUSTER-MODEL CALCULATIONS OF HYPERFINE PARAMETERS AND G-VALUE FOR DEFECTS IN A-SI-H

We have calculated the Si-29 hyperfine parameters using the density-fu nctional theory and g values using an iterative extended Huckel theory for defects in Si clusters. We confirm from these calculations that t he ESR signal with g = 2.0055 and the g = 2.0043- and 2.012-components of the light-induced ESR signal in a-Si:H originate from neutral thre efold-coordinated Si atoms and negatively and positively charged weak Si-Si bonds, respectively. (C) 1998 Elsevier Science B.V. All rights r eserved.