Based on the fequency calculations via a valence force field in a previous paper [1] , the MNDO quantum chemistry method is used to calculate the oscillator strengths of the twelve IR-active vibrational modes of the five configurations produced respectively by two models (vacancy+4H and interstitial silane) for the defect-complex corresponding to 2210 cm -1 absorption peak in the silicon crystal containing hydrogen. The calculation results show that the vacancy+4H model is preferable. In the light of the calculation results of the potential functions of A vibrational modes for the Si 16 H, Si 16 H 3 , S 16 H 4 and Si 14 H 4 atom clusters by the MNDO method, the reasonableness of oscillator strength calculations based on the frequency calculations with a valence force field method and the factors affecting the frequencies of the stretching vibrational absorption of the Si-H bonds are discussed. In addition, the experimental results proving the theoretical prediction are presented.
Read full abstract