The coupled system (2)²Σ⁺ and (1)²Π of ⁷Li⁸⁸Sr

Abstract

We analyse rovibrational transitions of the (2)2Σ+–X(1)2Σ+ system of LiSr and find the energy levels of the (2)2Σ+ state to be perturbed by coupling between the (2)2Σ+ and (1)2Π states. We present an analysis of the coupled system yielding molecular parameters for the lowest vibrational levels of the (2)2Σ+ state and for higher vibrational levels of the (1)2Π state together with molecular coupling constants. Improved Dunham coefficients for the rovibrational levels of the X(1)2Σ+ state are also obtained, where the correlation with the parameters of the excited states is removed completely.

The electronic system $(2)^2Σ^+$ and $(1)^2Π$ of LiCa

“…With the expansion of the rovibrational quantum numbers of the (2) 2 Σ + state, the range of the derivable analytical potential is enlarged. By the detailed study, local perturbations for all vibrational states are detected, which arise due to spin-orbit interactions between the states (2) 2 Σ + and (1) 2 Π as already reported for LiSr [13]. This leads to important information on the (1) 2 Π state and to the experimental determination of the sign of the spin-rotation splitting, not derivable from the data in ref.…”

“…Analogously to the molecules KCa [14], LiSr [12,13] and LiCa investigated in this study, other alkali-metal alkaline-earth-metal molecules can be investigated in the same way. For example, the RbSr molecule currently used to generate ultracold molecules [20,21] can be produced analogously in a heat pipe and examined with high-resolution spectroscopy using LIF experiments.…”

“…For the analysis of the coupling we use the Hamiltonian represented by the matrix in Hund's coupling case (a) with the three basis vectors | 2 Σ + , vΣ, J, e/f >, | 2 Π 1/2 , vΠ, J, e/f >, and | 2 Π 3/2 , vΠ, J, e/f > shown in Table 1. The Hamilton operator was discussed for the case of LiSr in our previous work [12] and [13], and contains the spin-orbit and rotational coupling of the two states following the development in the textbook by Lefebvre-Brion and Field [16].…”

“…In our research group, the molecules LiCa [10,11], LiSr [12,13] and KCa [14] were generated in a heat pipe oven and investigated with high resolution spectroscopy using laser-induced fluorescence (LIF). For the LiCa molecule, the analytical potential and the Dunham description of the ground state X(1) 2 Σ + (up to v"= 19) were reported in ref.…”

Electronic Spectroscopy and Photoionization of LiMg

“…There have been many theoretical and experimental studies of the Alk-AE dimers. − ,,− As the present study is focused on LiMg, we briefly summarize the gas-phase spectroscopic work that has been carried out on the Li-AE series. Electronic spectra have been recorded for LiBe, LiMg, , LiCa, ,, LiSr, ,, and LiBa. , With the exception of LiMg, a subset of the spectra for each dimer has been recorded at the level of rotational resolution. All of the dimers have X1 2 Σ + ground states.…”