Ce10[Si10O9N17]Br, Nd10[Si10O9N17]Br and Nd10[Si10O9N17]Cl oxonitridosilicate halides with a new layered structure type
Ce10[Si10O9N17]Br, Nd10[Si10O9N17]Br and Nd10[Si10O9N17]Cl oxonitridosilicate halides with a new layered structure type
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DOI：
10.1016/j.jssc.2005.08.010
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发表时间：
2005-11
影响因子：
3.3
通讯作者：
A. Lieb;W. Schnick
中科院分区：
文献类型：
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作者：
A. Lieb;W. Schnick
Ce{sub1}[Si{sub1}O{sub9}N{sub17}]Br，Nd{sub1}[Si{sub1}O{sub9}N{sub17}]Br和ND{sub1}[Si{sub1}O{sub9}N{sub17}]Cl是由相应的稀土金属及其氧化物和卤化物在1800℃左右的射频炉中与‘Si(NH){sub2}’反应得到的。C，使用CsBR，分别为.CSCL，作为助熔剂。经X-射线单晶衍射法测定其晶体结构为：a=10.6117(9)A，b=11.2319(10)A，c=11.688(8)A，r1=0.0356；Nd/BrA=10.523(2)A，b=11.101(2)A，c=11.546(2)A，r1=0.0239；NdCl：a=10.534A，b=11.109(2)A，c=11.543(2)A，r1=0.0253。根据Paulings规则，利用O/N分布模型进行了结构修正，即氮被定位在所有桥位上，而混合O/N占据在末端位置上，从而导致化合物的电荷中性。这些层由Q{sup 2}和Q{sup 3}型的[SiN{sub2}(O/N){sub2}]和[SiN{sub3}(O/N)]四面体组成。化合物的化学成分由三种化合物的化学分析和电子探针分析(EPMA)确定。报道了红外光谱研究的结果。
The isotypic oxonitridosilicate halides Ce{sub 1}[Si{sub 1}O{sub 9}N{sub 17}]Br, Nd{sub 1}[Si{sub 1}O{sub 9}N{sub 17}]Br and Nd{sub 1}[Si{sub 1}O{sub 9}N{sub 17}]Cl were obtained by the reaction of the respective lanthanide metals, their oxides and halides with 'Si(NH){sub 2}' in a radiofrequency furnace at temperatures around 1800 deg. C, using CsBr, resp. CsCl, as a flux. The crystal structures were determined by single-crystal X-ray diffraction (Pbam, no. 55, Z=2; Ce/Br: a=10.6117(9) A, b=11.2319(10) A, c=11.688(8) A, R1=0.0356; Nd/Br: a=10.523(2) A, b=11.101(2) A, c=11.546(2) A, R1=0.0239; Nd/Cl: a=10.534(2) A, b=11.109(2) A, c=11.543(2) A, R1=0.0253) and represent a new layered structure type. The structure refinements were performed utilizing an O/N-distribution model according to Paulings rules, i.e. nitrogen was positioned on all bridging sites and mixed O/N-occupation was assumed on the terminal sites resulting in charge neutrality of the compounds. The layers consist of condensed [SiN{sub 2}(O/N){sub 2}] and [SiN{sub 3}(O/N)] tetrahedra of Q{sup 2} and Q{sup 3} type. The chemical composition of the compounds was derived from chemical analyses for Nd{sub 1}[Si{sub 1}O{sub 9}N{sub 17}]Br and electron probe micro analyses (EPMA) for all three compounds. The results of IR spectroscopic investigations are reported.