The DNF Ã2A′-X̃2A″ Band System: Rotational Analysis of the Origin Band and Partial Analysis of Several Higher Bands

✍ Scribed by J. Chen; P.J. Dagdigian

• Publisher: Elsevier Science
• Year: 1993
• Tongue: English
• Weight: 751 KB
• Volume: 162
• Category: Article
• ISSN: 0022-2852
• DOI: 10.1006/jmsp.1993.1275

✦ Synopsis

The laser fluorescence excitation spectrum of the (0_{0}^{0}) band of the DNF (\dot{A}^{2} A^{\prime}-\dot{X}^{2} A^{\prime \prime}) system was obtained and rotationally analyzed. The (K_{u}^{\prime \prime}=0-4) subbands were recorded at (0.06 \mathrm{~cm}^{-1}) resolution. while higher subbands (\left(K_{a}^{\prime \prime} \leqslant 7\right.) ) were obtained at lower resolution (\left(0.2 \mathrm{~cm}^{-1}\right.) ). The assigned lines in this band were fitted to obtain rotational, centrifugal distortion, and spin-rotation parameters for the zero-point levels of the (\dot{A}^{2} A^{\prime}) and (\dot{X}^{2} A^{\prime \prime}) electronic states. Combining these rotational constants with those previously derived by Woodman [J. Mol. Spectrosc. 33, 311-344 (1970)] from analysis of the analogous HNF band allowed estimation of the mean geometries in both electronic states independent of any assumptions about bond lengths. Fluorescence excitation scans were also taken over the (2{ }{0}^{4}, 2{ }{0}^{3} 30_{0}^{1}), and (2{ }{0}^{6}) bands. The (K) structure in these bands is simpler because fluorescence can be detected only for excitation of the (K^{\prime}=0) and 1 stacks. Fits of measured line positions in the (K{a}^{\prime}=0-K_{a}^{\prime \prime}=1) subband allowed estimation of (\left(B^{\prime}+C^{\prime \prime}\right) / 2) for the upper vibrational levels of these bands. ic 1993 Academic Press. Inc.