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La_6NiSi_2S_(14)与La_6CoSi_2S_(14)单晶是利用助熔剂法在1100℃下合成的。它们皆属于六方晶系,P6_3空间群。a=10.293(1)[10.290(2)] A,c=5.744(1)[5.763(2)]A,Z=1。627[629]条反射(I≥2.5σ(I))参加计算,R=0.0363[0.0781]。La在扭曲的二帽三角棱柱内,与S八配位,La-S平均键长为2.990[2.992]A。Ni[Co](处于B位)在三角反棱柱里,与S六配位,Ni[Co]-S健长三个是2.559[2.529]A,其余三个为2.650[2.679]A,其占有率约为1/6。Si(处于C位)在四面体内,与S四配位,在Si-S键长中三个是2.130[2.146]A.第四个键长是2.098[2.093]A。
La_6NiSi_2S_ (14) and La_6CoSi_2S_ (14) single crystals were synthesized by flux method at 1100 ℃. They belong to the hexagonal system, P6_3 space group. A = 10.293 (1) [10.290 (2)] A, c = 5.744 (1) [5.763 (2)] A and Z = 1.627 [629] R = 0.0363 [0.0781]. La in the twisted two-cap triangular prism with S eight octahedral, La-S average bond length of 2.990 [2.992] A. Ni [Co] (at the B site) is in the triangular antiprism and is coordinated with S 6, 2.559 [2.529] A for Ni [Co] -S and 3.650 [2.679] A for the remaining three Rate is about 1/6. Si (at the C site) is tetrahedrally coordinated to S, three of which are 2.130 [2.146] A on the Si-S bond length and the second bond length is 2.098 [2.093]