| Autor: |
Ladjimi H; Laboratory of Interfaces and Advanced Materials, Faculty of Science, University of Monastir, Monastir 5019, Tunisia., Bejaoui M; Laboratory of Interfaces and Advanced Materials, Faculty of Science, University of Monastir, Monastir 5019, Tunisia., Zrafi W; Laboratory of Interfaces and Advanced Materials, Faculty of Science, University of Monastir, Monastir 5019, Tunisia., Berriche H; Laboratory of Interfaces and Advanced Materials, Faculty of Science, University of Monastir, Monastir 5019, Tunisia.; Department of Mathematics and Natural Sciences, School of Arts and Sciences, American University of Ras Al Khaimah, Ras Al Khaimah, P.O. Box 10021, United Arab Emirates. |
| Abstrakt: |
Ab initio calculations of alkaline diatomic molecule interactions with alkaline atoms provide detailed information about their electronic structure, vibrational frequencies, and spectroscopic properties, which are difficult to measure experimentally. This knowledge can aid in designing and interpreting experiments and guide the development of computational models and advanced dynamical calculation. Using the quantum chemistry ab initio methods based on multi-reference configuration interaction with Davidson correction (MCSCF/MRCI + Q), atomic effective core potentials, core-polarization potentials, and the interactions between the sodium atom and the NaRb diatomic molecule are investigated. To describe the potential energy surfaces of the RbNa 2 system, we introduce two geometries described in the Z-matrix coordinates ( R e , R , θ). Potential energy surfaces of the ground state 1 2 A' and the first excited state 2 2 A' were calculated for different approach directions of the sodium atom to the NaRb molecule and two geometries were considered. The first geometry is where the Na atom approaches the Rb atom of the RbNa dimer, and the second one is when it approaches the Na atom of the RbNa dimer. Global minima of the ground and first excited states and conical intersections between these states are determined for both geometries. The RbNa dimer in interaction with the sodium atom is found to be strongly attractive in its first excited state, which may be important for the experimenters particularly in the field of cold alkali polar dimers. Thereafter, the potential energy curves correlated to the lowest-lying dissociation limits are calculated in the linear form for the two geometrical cases (angle θ at 180°) and the atomic arrangement effect is observed. |
