New Low-Lying Electronic States of LaF

The (1)3Π Electronic State of LaF

“…Results were recently reported for the singlet systems (2) 1 + → X 1 + and (1) 1 → X 1 + (2), and for the triplet system [11.7] 3 → (1) 3 (3). In the present paper we give accurate effective spectroscopic constants for the (1) 3 state resulting from the study of transitions from the levels v = 0, 1, 2 of this state to levels of the (1) 3 state and of the ground state ((1) 3 1 → X 1 + transitions).…”

“…Resolutions of 0.020 to 0.060 cm −1 were achieved in the spectral region investigated, from 4500 to 12 000 cm −1 (1). The numerous bands observed were grouped into six systems involving the already known X 1 + , (1) 3 , (1) 1 , and (2) 1 + states and four states characterized for the first time, (1) 3 , (1). Extensive rovibrational analyses of these spectra were undertaken.…”

The (1)1Π, (2)1Σ+ → X1Σ+ Transitions of LaF

“…Two singlet-singlet systems and a triplet-singlet system involving X 1 ⌺ ϩ , and three triplet-triplet systems with (1) 3 ⌬ as lower state, have been observed. Preliminary rovibrational analyses have been carried out, allowing the low-lying (1) 3 ⌸ and (1) 1 ⌸ states from the 5d6s configuration, and at higher energies, a 3 ⌽ and the components ⍀ ϭ 0 Ϯ of a 3 ⌸ state to be characterized for the first time.…”

“…Two singlet-singlet systems and a triplet-singlet system involving X 1 ⌺ ϩ , and three triplet-triplet systems with (1) 3 ⌬ as lower state, have been observed. Preliminary rovibrational analyses have been carried out, allowing the low-lying (1) 3 ⌸ and (1) 1 ⌸ states from the 5d6s configuration, and at higher energies, a 3 ⌽ and the components ⍀ ϭ 0 Ϯ of a 3 ⌸ state to be characterized for the first time. We report in this note the results of a comprehensive study of (i) the (2) 1 ⌺ ϩ 3 X 1 ⌺ ϩ system, centered at about 11 662 cm Ϫ1 , which has been known for a long time (2) (only the bands (0 -0) and (0 -1) previously described are observed in our experiments), and (ii) the (1) 1 ⌸ 3 X 1 ⌺ ϩ system at 8455 cm Ϫ1 , in which 37 bands involving the vibrational levels Ј ϭ 0 to 9 and Љ ϭ 0 to 10 are rotationally analyzed.…”

“…The infrared thermal emission of the LaF molecule has recently been investigated at high resolution using a Fourier transform spectrometer (1). Two singlet-singlet systems and a triplet-singlet system involving X 1 ⌺ ϩ , and three triplet-triplet systems with (1) 3 ⌬ as lower state, have been observed.…”