C. Amiot

The X1Σg+ electronic state of K2

Abstract Laser induced fluorescence spectra of the A 1 Σ u + → X 1 Σ g + system have been recorded by Fourier transform spectrometry. The ground electronic state of the 39 K 2 molecule is characterized up to v = 75, encompassing 99.3% of the potential depth. A long-range study of the potential energy curve gave the coefficients of the multipolar expansion and the dissociation energy is found to be D e = 4451 ± 1.5 cm −1 (0.5519 ± 0.0002 eV).

The Cs2 A1Σu+ → X1Σg+ fluorescence excited by the Ar+ 1.09-μm laser line

Abstract Infrared fluorescence of Cs 2 in the region 8300 to 10100 cm −1 , which arises when levels of the A 1 Σ u + electronic state are pumped by the 1.09-μm line of an Ar + laser, has been recorded at high resolution by Fourier transform spectrometry. It is assigned to the system A 1 Σ u + → X 1 Σ g + . Constants for the A 1 Σ u + state of Cs 2 are (for 0 ≤ v ≤ 9) T e ( cm −1 ) ω e ( cm −1 ) ω e x e ( cm −1 ) B e ( cm −1 ) R e ( A ) 9627.06 36.09 0.375 9.06 10 −3 5.292

Laser-induced fluorescence and Fourier transform spectroscopy of TiO : an improved description of the 3Δ ground state

Abstract Laser-induced fluorescence spectra of the C 3 Δ- X 3 Δ and B 3 Π- X 3 Δ transitions of TiO have been recorded at high resolution by Fourier transform spectroscopy. For the molecule production, a simple flame reaction device was used. This device was based on a titanium hollow cathode sputtering source used with O 2 or N 2 O as oxidant. Experimental data involving vibrational progressions up to v ″ = 6 have been fitted with standard Hamiltonian matrix models, allowing for an improved description of the ground state. Moreover, a merged fit combining new LIF-data and previous high-resolution emission data on the B - X band system has been performed, yielding the best set of ground state molecular constants for TiO available to this date.

Ar+ laser-induced fluorescence spectra of Cs2: The E1Σu+ and (1) 1Πg electronic states

Abstract Laser-induced fluorescence of Cs2 molecules in the infrared (1.15–2.5 μm) and the visible (505–545 nm) regions has been observed using several excitation wavelengths from an argonion laser. Accurate molecular constants and potential energy curves for the pumped E1Σu+ state and the first excited gerade 1Π state are derived from more than 1300 fluorescence lines precisely measured with a high-resolution Fourier transform interferometer. The main molecular constants for the states are T e ( cm −1 ) ω e ( cm −1 ) B e ( cm −1 ) R e ( A ) E 1 Σ u + 20195.23 29.10 0.00891 5.340733 (1) 1 Π g 13913.42 18.44 0.00781 5.697722

The KRb electronic state

Abstract High-resolution spectra of the (3) 1 Π →(2) 1 Π system of the KRb molecule, obtained after excitation with fixed Ar+ laser frequencies, were recorded on a Connes-type Fourier transform interferometer. Our spectral observations led to the reassignment by 6 quanta of the vibrational numbering for the (2) 1 Π state reported by Kasahara et al. [J. Chem. Phys. 111 (1999) 8857]. Molecular constants of the first 19 vibrational levels of the (2) 1 Π state are determined by mixing the present work results and those of Kasahara et al. The potential energy curve is derived. The main spectroscopic constants for this highly perturbed electronic state of the 39 K 85 Rb isotopic species are: Te=15 902.06 (0.18) cm−1; ωe=49.76 (0.17) cm−1; Be=0.02438 (5) cm−1; Re=5.088 A; De=1358.19 (0.80) cm−1.

Fourier spectroscopy of the Asundi system (a′3Σ+-a3Π) of 13C16O

Abstract The Asundi system ( a ′ 3 Σ + - a 3 Π) of 13 C 16 O has been studied between 3500 and 12 000 cm −1 by high-resolution Fourier transform spectroscopy. The 10 bands, 0-0, 0−1, 1−0, 1−1, 1−2, 2−0, 2−1, 3−0, 4−0, and 4−2, were analyzed taking into account the strong perturbations appearing in the a ′ 3 Σ + ( v = 0,…,4) levels. Accurate perturbation parameters were obtained for all interacting states.

The first two excited 1Σg+ states of Cs2

Abstract Laser-induced fluorescence Of Cs 2 molecules in the infrared region (4000–9000 cm −1 ) has been observed using several exciting wavelengths from an argon-ion laser and from a ring dye laser. Accurate molecular constants for the first two excited 1 Σ g + electronic states are derived from spectra recorded at high resolution by Fourier transform spectroscopy. Main molecular constants are: (2) 1 Σ g + : T c = 12114.090 cm −1 , ω e = 23.350 cm −1 , B c = 7.4.5 × 10 −3 cm −1 , R c = 5.8316 A; (3) 1 Σ g + : T e = 15975.450 cm −1 , ω e = 22.423 cm −1 , B e = 8.23 × 10 −3 cm −1 , R c = 5.5569 A.

Analysis of spectra obtained by cold-atom photoassociation spectroscopy: the Rb2 1g and 0g− electronic states up to 100 Å

Abstract From the published spectra of states of Rb2 that lie within 35 cm −1 of the 5 2 S 3 2 + 5 2 P 3 2 dissociation limit it has been possible to derive the complete potential energy curves for the lg state (correlated to 1 II g at short intemuclear distance) and for the novel 0 g − ‘pure long-range’ state, predicted by ab initio calculations. Reliable values of dissociation limit constants v D and C 3 are derived and compared to the predictions of theoretical works.

The 13C2 and 12C13C Ballik-Ramsay system

Abstract The infrared spectrum of the b 3 Σ − → a 3 Π Ballik-Ramsay system has been observed for both 13 C 2 and 12 C 13 C isotopic species using high-resolution Fourier transform spectroscopy. Twelve bands: 0 → 0, 1 → 0, 1 → 1, 2 → 0, 2 → 1, 3 → 1, 3 → 2, 4 → 2, 4 → 3, 5 → 2, 5 → 3, 6 → 3 of 13 C 2 and seven bands: 0 → 0, 1 → 0, 1 → 1, 2 → 0, 2 → 1, 3 → 1, 3 → 2 of 12 C 13 C were identified in the spectral range 3500–12 000 cm −1 . Perturbations in the b 3 Σ − ( v = 0, 1, 2, 3) levels were reduced and accurate perturbation parameters derived from the analysis. A comparison with ab initio calculated spin-orbit coupling constants is presented.