摘要
It is verified that the phonon scattering process and the residual linewidthare the dominant factors of the linewidth of 2210 cm^(-1) IR absorption peak except the anomalous linewidth at 200 K. By investigating the anomalities of the peak shape and thelinewidth of the peak at 200 K, we put forward a mechanism that the T_d symmetry of defect-complex corresponding to the 2210 cm^(-1) peak can he transferred into the D_(2d) symmetry as temperature rises to above 200 K. The quantitative analysis shows that the V+4H-model is indeed of two states: The T_d configuration is stable at temperature lower than 200 K, while the D_(2d) one is stable at temperature higher than 200 K. We can draw the conclusion that the V +4H-model corresponds to the 2210 cm^(-1) IR absorption peak from the symmetric breaking mechanism, which can quantitatively fit the experimental results.
It is verified that the phonon scattering process and the residual linewidthare the dominant factors of the linewidth of 2210 cm<sup>-1</sup> IR absorption peak except the anomalous linewidth at 200 K. By investigating the anomalities of the peak shape and thelinewidth of the peak at 200 K, we put forward a mechanism that the T<sub>d</sub> symmetry of defect-complex corresponding to the 2210 cm<sup>-1</sup> peak can he transferred into the D<sub>2d</sub> symmetry as temperature rises to above 200 K. The quantitative analysis shows that the V+4H-model is indeed of two states: The T<sub>d</sub> configuration is stable at temperature lower than 200 K, while the D<sub>2d</sub> one is stable at temperature higher than 200 K. We can draw the conclusion that the V +4H-model corresponds to the 2210 cm<sup>-1</sup> IR absorption peak from the symmetric breaking mechanism, which can quantitatively fit the experimental results.
