MRCI study of analytical potential energy function and spectroscopic parameters of B_2~+ molecule

The potential energy curve for the ground state and low-lying excited state of B~+_2 molecule have been computed using MRCI method and Dunning's correlation consistent basis aug-cc-pVQZ. By employing Huxley and Murrell-Sorbie function as well as least square fitting method, the analytical potential energy functions of the states are induced. Based on this, we calculate the spectroscopic parameters. Present study shows that Huxley function is better than Murrell-Sorbie function and can re-display the interaction between atoms well. The RMS errors between the fitted results and ab initio values are too little in comparison with the chemical accuracy 4.184 kJ/mol. It shows that the present analytical potential energy functions are accurate, and can be used to more investigations.