Local and bulk susceptibilities of Np intermetallics in their paramagnetic state

Moessbauer-effect investigations under applied magnetic field and magnetization studies of neptunium intermetallics in their paramagnetic state are reported. It is shown that the bulk and local susceptibilities at 4.2 K ({chi}{sub {ital B}} and {chi}{sub {ital L}}, respectively) agree even for highly hybridized 5{ital f}-electron systems. The results indicate dominant orbital contributions to the magnetic moment also for paramagnetic neptunium heavy-fermion compounds. For these Np systems proportionalities between {chi}{sub {ital L}}, {chi}{sub {ital B}}, density of states at the Fermi energy, and the isomer shift are pointed out.