Ab initio adiabatic and diabatic energies and dipole moments of the KH molecule

Ab initio diabatic and adiabatic calculations for francium hydride FrH

Explicit ab initio diabatic and adiabatic calculations of potential energy curves (PECs) of the states ^1,3Σ⁺, ^1,3Π, and ^1,3Δ of francium hydride FrH have been carried out with several approaches.

Adiabatic and Diabatic Investigation of Numerous Electronic States for the Alkali Dimer FrNa

The current paper reports a global investigation of all excited states below the ionic limit Fr⁺Na^- of FrNa molecule following diabatic and adiabatic representations. The adiabatic and diabatic potential energy curves (PECs) for Σ⁺, Π, and Δ symmetries have been calculated for a dense grid of internuclear distances. The transition and permanent dipole moments (TDM and PDM) have been reported for both representations. Regarding the pseudopotential approach and full valence configuration interaction (FCI), the ab initio computation has been performed. Furthermore, the diabatization method was achieved by the use of the variational effective Hamiltonian theory (VEH). This latter served to assess the nonadiabatic coupling between the treated adiabatic states and to eliminate it employing a suitable unitary transformation matrix. The detailed computation of the PECs and PDM and TDM curves of the ground and excited states play a key role to coordinate experimental efforts in order to create cold and ultracold molecules in their ground stable rovibrational levels.

ab Initio Diabatic energies and dipole moments of the electronic states of RbLi molecule

For all states dissociating below the ionic limit Li(-) Rb(+) , we perform a diabatic study for (1) Σ(+) electronic states dissociating into Rb (5s, 5p, 4d, 6s, 6p, 5d, 7s, 4f) + Li (2s, 2p, 3s). Furthermore, we present the diabatic results for the 1-11 (3) σ, 1-8 (1,3) Π, and 1-4 (1,3) Δ states. The present calculations on the RbLi molecule are complementary to previous theoretical work on this system, including recently observed electronic states that had not been calculated previously. The calculations rely on ab-initio pseudopotential, core polarization potential operators for the core-valence correlation and full valence configuration interaction approaches, combined to an efficient diabatization procedure. For the low-lying states, diabatic potentials and permanent dipole moments are analyzed, revealing the strong imprint of the ionic state in the (1) Σ(+) adiabatic states. The transition dipole moment is used to evaluate the radiative lifetimes of the vibrational levels trapped in the 2 (1) Σ(+) excited states for the first time. In addition to the bound-bound contribution, the bound-free term has been evaluated using the Franck-Condon approximation and also exactly added to the total radiative lifetime.

Spectroscopic study of the B (1)Pi state of (39)KH

The B (1)Pi excited electronic state of (39)KH has been observed for the first time by a pulsed fluorescence excitation spectroscopic technique. We have found only one vibrational level, in which seven e-parity and seven f-parity sublevels are identified. The Dunham-type coefficients A(00), A(01), and A(02) and the mean internuclear separation for the B (1)Pi state have been derived. Their numeric values are separately 27 682.64(1) cm(-1), 1.533(1) cm(-1), -0.001 25(2) cm(-1), and 3.345(1) A for the B (1)Pi(+) state; 27 682.66(2) cm(-1), 1.532(2) cm(-1), -0.001 20(3) cm(-1), and 3.347(2) A for the B (1)Pi(-) state. The dissociation energy D(0) is determined to be 131.4(7) cm(-1). The vibrational frequency and the dissociation energy for the B (1)Pi state have also been estimated and the results are compared with recent ab initio calculations.