The (1)3Π Electronic State of LaF

✍ Scribed by A. Bernard; C. Effantin; E.A. Shenyavskaya; J. d'Incan

• Publisher: Elsevier Science
• Year: 2001
• Tongue: English
• Weight: 129 KB
• Volume: 207
• Category: Article
• ISSN: 0022-2852
• DOI: 10.1006/jmsp.2001.8334

✦ Synopsis

Rotational studies of bands of the infrared systems (1) 3 → (1) 3 and (1) 3 1 → X 1 + of lanthanum monofluoride were carried out with the aim of characterizing the (1) 3 state, assuming the previous representations of X 1 + and (1) 3 (1-3). The vibrational levels of (1) 3 involved in the analyzed transitions were v = 0, 1, 2 of the = 0 component, v = 0, 1 of the = 1 component, and v = 0 of the = 2 component. Perturbations were observed in both systems which were ascribed to spin-uncoupling interactions between (1) 3 2 (v = 0) and (1) 3 1 (v = 1) levels. A 9 × 9 matrix representation at equilibrium of the complex of interacting levels (v = 0, 1, 2) was constructed, each diagonal v-block corresponding to a triplet model of the rovibrational 3 Hamiltonian. The wavenumbers of some 1910 lines in the two systems were simultaneously fitted (rms error of the fit of about 0.0053 cm -1 ), thus yielding a consistent set of accurate spectroscopic constants for the (1) 3 state; the spin-uncoupling interaction parameter was determined as B 0,1 = 0.010917(13) cm -1 .