Accurate adiabatic correction for the hydrogen molecule using the Born-Handy formula

The adiabatic correction has been computed for the ground state of the hydrogen molecule at R = 1.4 bohr using the formula suggested by Handy — that avoids the specification of the relative coordinates — and Gaussian geminal wavefunctions. It is demonstrated that this method allows one to obtain easily very accurate results. The computed value for H2 has an accuracy of 10−4 cm−1.