title: Fourier-transform spectroscopy and deperturbation analysis of the spin-orbit coupled A(1)Σ(+) and b(3)Π states of KRb.
abstract: Fourier-transform A(1)Σ(+) - b(3)Π → X(1)Σ(+) laser-induced fluorescence spectra were recorded for the natural mixture of (39,41)K(85,87)Rb isotopologues produced in a heatpipe oven. Overall 4200 rovibronic term values of the spin-orbit coupled A(1)Σ(+) and b(3)Π states were determined with an uncertainty of about 0.01 cm(-1) in the energy range [10 850, 14 200] cm(-1) covering rotational quantum numbers J' ∈ [3, 280]. Direct deperturbation analysis of the A ∼ b complex performed within the framework of the A(1)Σ(+) ∼ b(3)ΠΩ=0,1,2 coupled-channel approach reproduced experimental data with a standard deviation of 0.004 cm(-1). Initial parameters of the internuclear potentials and spin-orbit coupling functions along with the relevant transition dipole moments were obtained by performing the quasi-relativistic electronic structure calculations. The mass-invariant molecular parameters obtained from the fit were used to predict energy and radiative properties of the A ∼ b complex for low J levels of (39)K(85)Rb as well as for (41)K(87)Rb isotopologues, allowing us to identify the most reasonable candidates for the stimulated Raman transitions between the initial uppermost vibrational levels of the a(3)Σ(+) and X(1)Σ(+) states, the intermediate levels of the A ∼ b complex, and the lowest absolute ground X(1)Σ(+)(v = 0, J = 0) state.
authors.affiliation: Laser Center, University of Latvia, 19 Rainis Boulevard, Riga LV-1586, Latvia.
authors.forename: K
authors.initials: K
authors.lastname: Alps
authors.affiliation: Laser Center, University of Latvia, 19 Rainis Boulevard, Riga LV-1586, Latvia.
authors.forename: A
authors.initials: A
authors.lastname: Kruzins
authors.affiliation: Laser Center, University of Latvia, 19 Rainis Boulevard, Riga LV-1586, Latvia.
authors.forename: M
authors.initials: M
authors.lastname: Tamanis
authors.affiliation: Laser Center, University of Latvia, 19 Rainis Boulevard, Riga LV-1586, Latvia.
authors.forename: R
authors.initials: R
authors.lastname: Ferber
authors.affiliation: Department of Chemistry, Lomonosov Moscow State University, Leninskie gory 1/3, 119991 Moscow, Russia.
authors.forename: E A
authors.initials: EA
authors.lastname: Pazyuk
authors.affiliation: Department of Chemistry, Lomonosov Moscow State University, Leninskie gory 1/3, 119991 Moscow, Russia.
authors.forename: A V
authors.initials: AV
authors.lastname: Stolyarov