Self-Polarization Contribution to Magnetic Ordering in Systems with Singlet Ground State

Self-polarization effects on the $f$-electron magnetization is found to contribute significantly to the susceptibility and critical value of the exchange for ordering of the rare-earth group-V intermetallic compounds where the ground state of the rare-earth ion is a crystal-field singlet. For PrBi, a typical example of such a system, the contribution from the self-polarization effect is found to be of the same order as the Ruderman-Kittel-Kasuya-Yosida contribution.