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要旨:
Li0.44Eu3[B3N6] was synthesized from the metathesis reaction of
Li-3[BN2] and EuCI3 at 850 degrees C. Li0.44EU3-[B3N6] crystallizes in
the trigonal space group R (3) over barc (No. 167) with a=12.0225(2)
angstrom, c=6.8556(2) angstrom and Z=6. In the crystal structure,
isolated, planar cyclic [B3N6](9-) units are charge-balanced by the
mixed-valence Eu3+/Eu2+ and Li+ cations. Li+ occupies partially (44%)
the Wyckoff site 6b and is sandwiched between the [B3N6](9-) anions.
Mossbauer spectroscopy results show the resonance lines of Eu2+ and
Eu3+, respectively, indicating the heterogeneous mixed valency of the Eu
atoms. X-Band ESR investigations between 5 and 300 K reveal an intense
signal over the whole temperature range originating from Eu2+. Magnetic
susceptibility measurements indicate a Curie-Weiss behavior with an
experimental effective magnetic moment of (mu eff)=8.28 (mu B) per
formula unit. (C) 2013 Elsevier Inc. All rights reserved.
