The laser induced fluorescence (LIF) spectra A 1 Σ + ∼ b 3 Π(E J ) → X 1 Σ + of KCs dimer were recorded in near infrared region by Fourier Transform Spectrometer with a resolution of 0.03 cm −1 . Overall more than 200 collisionally enhanced LIF spectra were rotationally assigned to 39 K 133 Cs and 41 K 133 Cs isotopomers yielding with the uncertainty of 0.003-0.01 cm −1 more than 3400 rovibronic term values of the strongly mixed singlet A 1 Σ + and triplet b 3 Π states. Experimental data massive starts from the lowest vibrational level vA = 0 of the singlet and nonuniformly cover the energy range E J ∈ [10040, 13250] cm −1 with rotational quantum numbers J ∈ [7, 225]. Besides of the dominating regular A 1 Σ + ∼ b 3 ΠΩ=0 interactions the weak and local heterogenous A 1 Σ + ∼ b 3 ΠΩ=1 perturbations have been discovered and analyzed. Coupled-channel deperturbation analysis of the experimental 39 K 133 Cs e-parity termvalues of the A 1 Σ + ∼ b 3 ΠΩ=0,1,2 complex was accomplished in the framework of the phenomenological 4 × 4 Hamiltonian accounting implicitly for regular interactions with the remote 1 Π and 3 Σ + states manifold. The resulting diabatic potential energy curves of the interacting states and relevant spin-orbit coupling matrix elements defined analytically by Expanded Morse Oscillators model reproduce 95% of experimental data field of the 39 K 133 Cs isotopomer with a standard deviation of 0.004 cm −1 which is consistent with the uncertainty of the experiment. Reliability of the derived parameters was additionally confirmed by a good agreement between the predicted and experimental termvalues of 41 K 133 Cs isotopomer. Calculated relative intensity distributions in the A ∼ b → X LIF progressions are also consistent with their experimental counterparts. Finally, the deperturbation model was applied for a simulation of pump-dump optical cycle a 3 Σ + → A 1 Σ + ∼ b 3 Π → X 1 Σ + proposed for transformation of ultracold colliding K+Cs pairs to their ground molecular state vX = 0; JX = 0.

No abstract

No abstract

The NaK 1 ( b ) Π Ω = 0 3 state hyperfine structure and the 1 ( b ) Π Ω = 0 3 2 ( A ) Σ + 1 spin-orbit interaction J. Chem. Phys. 122, 074306 (2005); 10.1063/1.1844293 High resolution spectroscopy and channel-coupling treatment of the A 1 Σ + -b 3 Π complex of NaRbWe present new c 3 ⌺ ϩ →a 3 ⌺ ϩ laser induced fluorescence spectra of the NaK molecule, which clearly indicate that v 0 ϭ20 is the first vibrational level of the c 3 ⌺ ϩ state lying above vϭ0 of B 1 ⌸ state. These spectra are used in a multistep deperturbation (B 1 ⌸ϳc 3 ⌺ ϩ ϳb 3 ⌸) procedure to obtain improved a 3 ⌺ ϩ , b 3 ⌸ and c 3 ⌺ ϩ potential energy curves. The deperturbation analysis is confirmed by the calculated electronic B 1 ⌸ϳc 3 ⌺ ϩ and c 3 ⌺ ϩ ϳb 3 ⌸ spin-orbit matrix elements obtained from many-body multipartitioning perturbation theory employing the relativistic effective potential method.

No abstract