Synthesis, crystal structure and magnetic properties of Li_0.44Eu₃[B₃N₆]

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• 作者：I. Kokal ; U. Aydemir ; Yu. Prots ; T. F枚rster ; J. Sichelschmidt ; M. Yahyaoglu ; G. Auffermann ; W. Schnelle ; F. Schappacher ; R. P枚ttgen ; M. Somer
• 关键词：Lithium ; Europium ; Cyclotrinitridoborate ; Crystal structure ; M&ouml ; ssbauer ; ESR
• 刊名：Journal of Solid State Chemistry
• 出版年：February, 2014
• 年：2014
• 卷：210
• 期：1
• 页码：96-101
• 全文大小：1474 K

文摘

Li_0.44Eu₃[B₃N₆] was synthesized from the metathesis reaction of Li₃[BN₂] and EuCl₃ at 850 掳C. Li_0.44Eu₃[B₃N₆] crystallizes in the trigonal space group (No. 167) with a=12.0225(2) 脜, c=6.8556(2) 脜 and Z=6. In the crystal structure, isolated, planar cyclic [B₃N₆]^{9鈭?/sup> 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鈭?/sup> anions. M枚ssbauer 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 渭_eff=8.28 渭_B per formula unit.}