Improvement of the Spectroscopic Constants of the PF(A3Π) State and Assignment of the PF(A–X) Transition Dipole Function

✍ Scribed by B. Nizamov; D.W. Setser

• Publisher: Elsevier Science
• Year: 2001
• Tongue: English
• Weight: 236 KB
• Volume: 206
• Category: Article
• ISSN: 0022-2852
• DOI: 10.1006/jmsp.2000.8278

✦ Synopsis

High-resolution laser-excitation spectra were acquired for the v = 3-7 levels of the PF(A 3 0,1,2 ← X 3 -) transition from PF(X 3 -) molecules generated in a discharge flow reactor. These results were combined with lower resolution excitation spectra for the v = 8-11 levels and with existing high-resolution data in the literature for v = 0 and 1 to assign improved spectroscopic constants for PF(A 3 0,1,2 ). The abnormal vibrational energy level spacings for all spin components of the PF(A 3 ) state are evidence for a homogeneous interaction with another 3 state. The -doublet separation in the PF( 3 0 ) substate increases with vibrational level, which is taken as evidence for interaction with the PF(b 1 + ) state. Laser-induced fluorescence spectra from individual v = 0-5 levels were used to obtain vibrational band intensities of the A-X transition. The strong dependence of the transition dipole on the r-centroid is consistent with the reduction in the radiative lifetimes with increasing v level. The similarity between the isovalent PF(A 3 ) and SO(A 3 ) states is noted and the bond dissociation energy of PF(X 3 -) is discussed.