Correlation, relativistic and adiabatic corrections to the ground state potential curve of the hydrogen molecule

Correlation, relativistic and adiabatic corrections are computed for the el ectronic ground state of the hydrogen molecule for r less than or equal to 12 a.u. In contrast to previous calculations (based on the numerical soluti on of the Schrodinger equation, mainly done by Wolniewicz et al.), our resu lts are based on the ordinary ab initio treatment using a lour-component wa ve function with fully relativistically reoptimized basis sets and adiabati c corrections by the treatment developed in our laboratory. The calculated energies are fitted to the polynomial/exponential analytical function and t he evaluated spectroscopic parameters are compared with those obtained in t he same manner from the Wolniewicz data. The results presented show a good agreement with exact numerical calculations published previously.