a-SrZn5-Type solid solution, BaZn2.6Cu2.4
a-SrZn5-Type solid solution, BaZn2.6Cu2.4
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a-SrZn5型固溶体、BaZn2.6Cu2.4
DOI：
10.1107/s2056989019012532
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发表时间：
2019
期刊：
影响因子：
--
通讯作者：
H Yamane
中科院分区：
文献类型：
--
作者：
R Simura;H Yamane
将Ba、Cu和Zn的金属片在Ar气氛中加热到973 K，然后缓慢冷却，得到标题化合物BaCu 2.6Zn 2.4的单晶。 X射线单晶结构分析表明，BaCu2.6Zn2.4为正交晶系[a = 12.9858（3），B = 5.2162（1），c = 6.6804（2）]，具有α-SrZn 5型结构（空间群Pnma）。 三维框架由Cu和Zn原子组成，其中Ba原子在b轴方向上延伸的隧道中。虽然Ba原子比Sr原子大，但BaCu2.6Zn2.4 [452.507（19）<$3]的晶胞体积比α-SrZn 5 [466.08 <$3]的晶胞体积小。 这种体积的减小可以归因于骨架中Cu原子被Zn原子部分取代，因为Cu-Zn和Cu-Cu键比Zn-Zn键短。Ba-Zn原子间距离从Sr-Zn距离的增加被Cu原子部分取代Zn所抵消，这导致平均Ba-Zn/Cu距离变短。
Single crystals of the title compound barium zinc copper, BaCu2.6Zn2.4, were obtained from a sample prepared by heating metal chips of Ba, Cu, and Zn in an Ar atmosphere up to 973 K, followed by slow cooling. Single-crystal X-ray structure analysis revealed that BaCu2.6Zn2.4 crystallizes in an orthorhombic cell [a = 12.9858 (3), b = 5.2162 (1), and c = 6.6804 (2) Å] with an α-SrZn5-type structure (space group Pnma). The three-dimensional framework consists of Cu and Zn atoms, with Ba atoms in the tunnels extending in the b-axis direction. Although the Ba atom is larger than the Sr atom, the cell volume of BaCu2.6Zn2.4 [452.507 (19) Å3] is smaller than that of α-SrZn5 [466.08 Å3]. This decrease in volume can be attributed to the partial substitution of Cu atoms by Zn atoms in the framework because the Cu—Zn and Cu—Cu bonds are shorter than the Zn—Zn bond. The increase in Ba—Zn interatomic distances from the Sr—Zn distances is cancelled out by the partial replacement of Zn with Cu atoms, which leads to shorter average Ba—Zn/Cu distances.