Vibrational frequencies of hydrazoic acid and methyl azide: density functional theory study

• 作 者: 周正宇 杜冬梅 付爱萍 俞庆森
• 机 构: Department of Chemistry, Qufu Normal University, Qufu, Shandong 273165 , China State Key Laboratory
• 出 处: Chinese Journal of Chemistry
• 发表日期: 2000年03期
• 关键词: azide vibrational deviation substitution Hartree absolute devoted bands Slater 关

Harmonic vibrational frequencies of HN3 and CH3N3 molecules and their several isotopomers are calculated using HF, MP2 and five popular density functional theory (DFT) methods. On the basis of the comparison between calculated and experimental results, assignments of fundamental vibrational modes arc examined. HF and MP2 results are in bad agreement with experimental values. Of the five DFT methods, BLYP reproduces the observed fundamental frequencies the most satisfactorily. Two hybrid DFT methods are found to yield frequencies generally higher than the observed fundamental frequencies. The results indicate that BLYP calculation is a very promising approach for understanding the observed spectral features.

Harmonic vibrational frequencies of HN3 and CH3N3 molecules and their several isotopomers are calculated using HF, MP2 and five popular density functional theory (DFT) methods. On the basis of the comparison between calculated and experimental results, assignments of fundamental vibrational modes examined by HF Of the five DFT methods, BLYP reproduces the observed fundamental frequencies the most satisfactorily. Two hybrid DFT methods are found to yield frequencies generally higher than the observed fundamental frequencies. The results indicate that BLYP calculation is a very promising approach for understanding the observed spectral features.