Ab initio calculations for the first-positive bands of N-2

作者：Ni, Chao; Cheng, Junxia; Cheng, Xinlu^*

来源：Journal of Molecular Spectroscopy, 2017, 331: 17-22.

DOI：10.1016/j.jms.2016.10.013

• Nitrogen molecules
• Ab initio
• Einstein A coefficient
• Transition dipole moment
• High temperature
• Absolute intensities

The absolute absorption spectral line intensities of the 0-0, 1-1, 2-2, 3-3, and 4-4 bands of N-2(A(3)Sigma(+)(u)-B (3)Pi(g)) are computed for the first time with the accurate potential energy curves (PECs) and transition dipole moment curves (TDMCs) using the ab initio calculation. During the calculation process, the precise multireference configuration interaction (MRCI) approach with the augmented correlation consistent polarized valence quadruple-zeta set (aug-cc-pVQZ) and active space 3110311 are used. The calculated PECs of the two states (A(3)Sigma(+)(u),B (3)Pi(g)) agree well with Rydberg-Klein-Rees (RKR) potential, and the calculated TDMCs are more reasonable than the results of other studies. Our calculated Einstein A coefficients are also well consistent with the recent experiment results. The intensities of five bands are obtained from the summation of their respective absolute line intensities, for instance, the 0-0 band intensities are 3.25 x 10(-16) cm(-1)/(molecule cm(-2)) at 300 K and 1.65 x 10(-16) cm(-1)/(molecule cm(-2)) at 3000 K. The theoretical results are credible. They are also beneficial for astrophysics where high temperature dominates.

• 出版日期2017-1
• 单位四川大学; 内江师范学院