[en] Ab initio CASSCF/MRCI calculations have been performed for the molecule LaCl, for 11 molecular states in the representation ^2S+1Λ^(+/-) (neglecting spin-orbit effects). The corresponding 25 molecular states in the representation Ω^(+/-) (including spin-orbit effects) have been subsequently determined using a semi-empirical spin-orbit pseudopotential built up for lanthanum. Calculated potential energy curves and spectroscopic constants are reported, to the best of our knowledge they are the first ones for excited states of this molecule. Comparison of present data with experimental results available in literature show a good agreement

[en] A theoretical study of the electronic structure of Rb₂⁺ has been performed, including or not spin-orbit (SO) coupling. Potential energy curves for all the molecular states dissociating up to the limit Rb⁺+Rb(7s ²S_1/2) (i.e., 26 states in the representation ²Λ⁽⁺⁾_g,u and 38 states in the representation Ω_g,u) are displayed. Equilibrium distances, transition energies and depths for the wells predicted at short and large range of R are reported. The existence of some of the long-range wells are confirmed by a specific model. Extensive tables of energy values versus internuclear distances are available at the following address: http://lasim.univ-lyon1.fr/allouche/rb2plus.htm

[en] We have realized a theoretical study of K Rb and Rb Cs dimers.The model used here is based on quantum chemistry methods of ab initio calculations. The potential curves are investigated using configuration-Interaction calculations with ab initio effective core potentials. The core-valence correlation is introduced into pseudopotential calculations by modifying the existing core polarization potential. The present theoretical results confirm the experimental determinations concerning the electronic structure of the ground states of Rb Cs and K Rb. (author). 16 Refs. 7 tabs

[en] Full text.Accurate calculations based on ab initio quantum mechanical method were carried out for small rubidium clusters Rbn (n=1-5) to determine their electronic and geometric structure. The detailed electronic structures of these clusters are studied. Stabilities from the point of view of binding and fragmentation energies are discussed. The LANL2DZ basis set is used for the optimization of molecular geometries. Geometries were optimized by minimizing the total energy within the KS (Kohn-Sham) formalism using the analytical technique. All computation were done by using Molpro program

[en] Ab initio potential-energy curves and radial and rotational coupling matrix elements have been calculated by means of configuration-interaction methods. A semiclassical treatment including electron translation factors has been performed in the (0.1--1.5)x10⁸ cm/s velocity range and provides a good agreement with experiment

[en] Full text.The advancement in photo association in ultracold alkali atom trapping and the recent use of the molecule KCs in quantum computer stimulated theoretical approaches to provide predictions accurate enough to be useful for interpretation and evenly for guidance of experiments. With the aim of improving the accuracy of predictions we will perform a theoretical study of the electronic structure of the molecule KCs, using a method mainly in the way by which core-valence effects are taken into account. The atoms K and Cs will be treated through non-empirical effective one electron core potentials of Durand and Barthelat type. Molecular orbitals for KCs will be derived from Self Consistent Field Calculations (SCF) and full valence Configuration Interaction (IC) Calculations. A core-core interaction more elaborated than the usual approximation 1/R will be taken into account as the sum of an exponential repulsive term plus a long range dispersion term approximated by the well known London formula. Potential energy calculations have been performed for different molecular states, for numerous values of the inter-nuclear distance R in a wide range. Spectroscopic constants have been derived for the bound states with a regular shape. A ro vibrational study have been performed for the ground states with a calculation of the rotational and centrifugal distortion constants

[en] Full text.The potential energy has been calculated over a wide range of internuclear distance for twenty-nine lowest states of symmetry Σ⁺, Π, Δ, Φ and Ω = 0, 1, 3, 4 of the molecule LaF. The comparison of the calculated spectroscopic constants with those obtained recently from experiment showed a good agreement. By replacing th ero-vibrational differential Scrodinger equation by a Volterra integral equation the wave function will be given by Ψ = Σ_i=0¹ a_if_i where the coefficients a_i are obtained from the boundary conditions of the wave function and f_i are two well defined canonical functions. Using these functions the eigenvalues E_v, the rotational constant B_v and the centrifugal distortion constants D_v have been calculated for the considered bound states up to v=34 as well as the electric and transition dipole moments for transitions between Σ⁺ and Π states. The comparison of the calculated Franck-Condon factors with those obtained experimentally showed an over all good agreement

[en] Full text.The advancement in photodissociation spectroscopy of alkali dimers and the very accurate high-resolution techniques stimulated theoretical approaches, necessary to provide predictions accurate enough to be useful for interpretation and evenly for guidance of experiments. With the aim of improving the accuracy of predictions we will perform a theoretical study of the electronic structure of the molecule LiRb, using a method mainly in the way by which core-valence effects are taken into account. To investigate the electronic structure of LiRb we will use the package CIPSI (Configuration Interaction by Perturbation of a multiconfiguration wave function Selected Interactively) of the Laboratoire de Physique Quantique (Toulouse, france). The atoms Li and Cs will be treated through non-empirical effective one electron core potentials of Durand and Barthelat type. Molecular orbitals for LiRb will be derived from Self Consistent Field Calculations (SCF) and full valence Configuration Interaction (IC) calculations. A core-core interaction more elaborated than the usual approximation 1/R will be taken into account as the sum of an exponential repulsive term plus a long range dispersion term approximated by the well known London formula. Potential energy calculations will be performed for different molecular states, for numerous values of the inter-nuclear distance R in a wide range. Spectroscopic constants have been derived for the bound states with a regular shape. A rovibrational study have been performed for the ground states with a calculation of the rotational and centrifugal distortion constants. A calculation for the transition dipole moment and matrix elements have been done for the bound states. An RKR potential have been determined for the bound states of the molecule LiRb obtained from an ab initio calculation

[en] Full text.The existence of new experimental data on the alkali dimers has stimulated theoretical approaches, necessary to provide predictions accurate enough to be useful for interpretation and evenly for guidance of experiments. With the aim of improving the accuracy of predictions we will perform a theoretical study of the electronic structure of the molecule NaCs using a method mainly in the way by which core-valence effects are taken into account. To investigate the electronic structure of NaCs we will use the package CIPSI (Configuration Interaction by Perturbation of a multiconfiguration wave function Selected Interactively) of the Laboratoire de Physique Quantique (Toulouse, France). The atoms Na and Cs will be treated through non-empirical effective one electron core potentials of Durand and Barthelat type. Molecular orbitals for NaCs will be derived from Self Consistent field Calculations (SCF) and full valence Configuration Interaction (IC) calculations. A core-core interaction more elaborated than the usual approximation 1/R will be taken into account as the sum of an exponential repulsive term plus a long range dispersion term approximated by the well known London formula. Potential energy calculations will be performed for different molecular states, for numerous values of the inter-nuclear distance R in a wide range. Spectroscopic constants have been derived for the bound states with regular shape. A ro vibrational study have been performed for the ground states with a calculation of the rotational and centrifugal distortion constants. A calculation for the transition dipole moment and matrix elements have been done for the bound states

[en] Full text.The present investigation is devoted to the prediction of the electronic spectrum of NaRb molecule as a member of group I. The existence of new experimental data on these species has stimulated theoretical calculations, necessary to provide predictions accurate enough to be useful for interpretation and evenly for guidance of experiments. A core-core interaction more elaborated than the usual approximation 1/R will be taken into account as the sum of an exponential repulsive term plus a long range dispersion term approximated by the well known London formula. With the aim of improving the accuracy of predictions we will perform a theoretical study on the electronic structure of the molecule NaRb, using a method mainly in the way by which core-valence effects are taken into account. Many transitions has been studied experimentally for the ground and excited states. We knew no previous theoretical study on the diatomic molecule NaRb with spin orbit effect. The present work was motivated by the lack of the theoretical data for NaRb. To investigate the electronic structure of the molecule NaRb the TLSE package have been used. Molecular orbitals for NaRb have been derived from Self Consistent field calculations (SCF). Potential energy calculations have been performed for different molecular states, for numerous values of the inter-nuclear distance R and Spectroscopic constants have been derived for the bound states with a regular shape. A ro vibrational study have been performed for the ground states with a calculation of the rotational and centrifugal distortion constants