Thesis & Dissertations

A theoretical investigation of the magnesium monofluoride (MgF) molecule is performed using ab initio calculations. The low-lying electronic states are determined by the Complete Active Space Self Consistent Field (CASSCF) followed by the Multireference Configuration Interaction (MRCI) including single and double excitations with Davidson correction (+Q). Ab initio Calculations were performed using the computational chemistry program MOLPRO taking advantage of the graphical user interface GABEDIT. In this research, the potential energy curves and the dipole moment curves have been investigated for the twenty seven low-lying electronic states in the 2s+1Λ± representation. The harmonic frequency We, the internuclear distance Re , the rotational constant Be , and the electronic energy with respect to the ground state Te have been calculated. By using the canonical functions approach, the vibrational energy Ev , the rotational constants Bv , the centrifugal distortion constants Dv , and the abscissas of turning points Rmin and Rmax have been determined for various vibrational levels of different electronic states of the molecule MgF. The comparison of our results with experimental and theoretical data for several states has demonstrated a good accuracy for our predictions. Twenty electronic states have been studied here for the first time.