Components of the magnetizability of the B’ ${}^1$${\Sigma }_u^{+}$ state of the hydrogen molecule have been calculated for a wide range of bond lengths. Explicitly correlated, ‘‘generalized James-Coolidge-type wave functions’’ were used. It is found that in the B’ ${}^1$${\Sigma }_u^{+}$ state the molecular magnetizability is a positive quantity for bond lengths near equilibrium due to the mixing in of the nearby $D^1$${\Pi }_u$ state by the magnetic field. As a result ‘‘van Vleck paramagnetism’’ exists in the lowest vibrational level of the B’ state. At larger bond lengths this mixing is reduced by increasing influence of the $C^1$${\Pi }_u$ state. The crossing of the potential curves of B’ and C states produces the singularity point on the ${\chi }_{\perp }^p$ curve. As a result the paramagnetism disappears for higher vibrational states. The long-range parts of the components of the magnetizability of the a ${}^3$${\Sigma }_g^{+}$ and B${}^1$${\Sigma }_u^{+}$ states of ${\mathrm{H}}_2$ also have been calculated in order to study the asymptotic behavior of the magnetizability at large bond length.

• Received 30 August 1984

DOI:https://doi.org/10.1103/PhysRevA.31.2091