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キーワード:
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要旨:
The hexagonal modification hP8 of the binary compound EuGe3 was obtained
by high-pressure high-temperature reaction at 12(1) GPa and 1100(110) K.
The compound adopts an Mg3Cd-type crystal structure, forming infinite
columnar units of germanium triangles in staggered conformation which
are stacked along the [ 001] direction. X-ray absorption spectroscopy
together with magnetic susceptibility measurements indicate the electron
configuration 4f(7)(2+) of the europium atoms. Chemical bonding analysis
reveals covalent bonding within the triangular Ge-3 units and between Eu
and Ge. Physical properties measurements indicate bad-metal type
electrical conductivity and an antiferromagnetic ordering of the
europium moments below 36(1) K. At 8 GPa and 1000 K, EuGe3 forms the
modification hR36.
