J. Phys. Soc. Jpn. 67, pp. 941-949 (1998) [9 Pages]

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Received August 25, 1997

We propose a theory of CeB _{6 } in a magnetic field by extending and slightly modifying a previous paper. The antiferro-quadrupolar ordering induces dipoles and octupoles when the magnetic field is applied. The nature of those field-induced multipoles is studied by changing the direction of the field. It is shown that the contradiction between NMR and neutron diffraction is resolved by taking into account the influence of octupoles. Thus it is concluded that CeB _{6 } is the first example in which the octupoles play a crucial role on the anomalous *f *-electron ordered phase.

©1998 The Physical Society of Japan

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