Characterization of the c3Σ(+) State of SCF - The c3Σ+-X1Σ+ System

✍ Scribed by E.A. Shenyavskaya; J. Verges; A. Topouzkhanian; M.A. Lebeaultdorget; J. Dincan; C. Effantin; A. Bernard

• Publisher: Elsevier Science
• Year: 1994
• Tongue: English
• Weight: 326 KB
• Volume: 164
• Category: Article
• ISSN: 0022-2852
• DOI: 10.1006/jmsp.1994.1061

✦ Synopsis

Thermal emission of scandium monofluoride has been spectroscopically investigated at high resolution in the region (7000-12000 \mathrm{~cm}^{-1}) with a Fourier transform spectrometer. The predicted low-energy (c^{3} \Sigma^{+})state is observed in a transition to the ground state; six bands of the (c^{3} \Sigma^{+}-X^{1} \Sigma^{+}) system. (0-0,0-1,0-2,1-0,1-3,2-0). are rotationally analyzed. Molecular constants are obtained for (c^{3} \Sigma^{+}(v=0,1,2)). The rotational dependence of the spin-splitting parameters (t) and (\gamma) is evaluated. Principal constants (in (\left.\mathrm{cm}^{-1}\right)) for (c^{3} \Sigma^{+}(v=0)) are (T=9384.59, B=0.34432, D=) (0.450 \times 10^{-6}, \epsilon=-16.00), and (\gamma=0.1132). In addition to the appearance of the forbidden transition (\left(^{3} \Sigma^{+}-X^{\prime} \Sigma^{+}\right.), some other consequences of the interaction (c^{3} \Sigma^{+} \sim B^{\prime} \Pi) are recognized: (i) the large values of (\mathrm{\epsilon}) and (\gamma) in (c^{3} \Sigma^{+})decrease markedly on going from (v=0) to (v=1), and at the same time, in (B^{\prime}) II the large (A)-doubling in (v=0) decreases rapidly in magnitude with increasing (v), and (ii) a broadening of the (Q) lines in (B^{\prime} I I(v=0)-X^{1} \Sigma^{+})bands correlated with a narrowing of ({ }^{P} Q) and ({ }^{R} Q) lines in (c^{3} \Sigma^{+}(v=0)-X^{1} \Sigma^{+})bands, both effects being attenuated in (v^{\prime}=1) bands and becoming unobservable in (v^{\prime}=2) bands which show sharp (Q) in the singlet-singlet system and intrinsically broadened ({ }^{P} Q) and ({ }^{R} Q) lines in the triplet-singlet system. 61994 Academic Press. Inc.