An ab initio study of the ground and first excited state of HCN ↔ HNC isomerization and a calculation of the HNC A → X fluorescence spectrum

✍ Scribed by B. Gazdy; D.G. Musaev; J.M. Bowman; K. Morokuma

• Publisher: Elsevier Science
• Year: 1995
• Tongue: English
• Weight: 397 KB
• Volume: 237
• Category: Article
• ISSN: 0009-2614
• DOI: 10.1016/0009-2614(95)00277-b

✦ Synopsis

We report ab initio calculations of the minima and transition states of the HCN ~ HNC isomerization in the X(P~) and A(/~') electronic states, and the A-X transition moment in the neighborhood of the HNC isomer. The HNC(A) potential is fit to a fourth-order Simons-Parr-Finlan force field, and the nuclear coordinate dependence of the A-X transition moment is fit to a polynomial in displacement coordinates. The A-X fluorescence spectrum is calculated using a rigorously calculated wavefunction for the HNC(A), the fitted transition moment, and hundreds of previously calculated HCN/HNC(X) vibrational wavefunctions, which were obtained using a previous global ab initio potential.