Ab initio calculation of vibrational frequencies of GexSe1−x glass

Density Functional Theory Calculation of Adsorption of NaCl on Chlorophyll

“…We have made considerable effort to obtain energies as well as vibrational frequencies in several systems. The calculated values are in reasonable agreement with the experimental values deduced from the Raman spectra [6][7][8][9][10].…”

Ab initio calculation of vibrational frequencies of AsO glass

“…This kind of first principles calculations are very useful in predicting electronic properties. Our calculations of vibrational frequencies appear to be in reasonable agreement with the experimental data [6][7][8]. The first principles calculations of the band structures of AgSbS, AgSbSe and AgSbTe are found to be useful for improving the thermoelectric properties [10], Similarly, it is found that DFT gives good results for the geometry optimization of PbTe [11].…”

“…We repeated the calculation of clusters of Ge x P x S 1À2x glass in as far as the structural parameters such as the bond lengths and the vibrational frequencies are concerned and found that clusters along with linear molecules are present in the glass [7]. The example of Ge x Se 1Àx also showed [8] that clusters such as Ge 4 Se 3 ; Ge 2 Se 2 ; Ge 3 ; GeSe 3 and Ge 3 Se 2 are present in the glass. Therefore, we believe that cluster calculations are important for the understanding of the glassy state.…”

Phonon driven transport in amorphous semiconductors: transition probabilities

“…Therefore the present work predicts that for different materials, the upper temperature limit T up of VRH is proportional to the frequencyν of the first peak in phonon spectrum. Figure 3 reports experimental data for a-Si [61], a-Ge [61,62], a-SiO 2 [63,64,65] and a-Cu 2 GeSe 3 [66,67]: the upper limit temperature T up of VRH vs. the first peak of phonon spectrumν. A linear relation between T up andν is satis-fied.…”