Constitution of network structures with large. inner spaces with antimonate ions

构成网络结构规模大。

基本信息

批准号：
18550050
负责人：
IMOTO Hideo
金额：
$ 2.63万
依托单位：
Utsunomiya University
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (C)
财政年份：
2006
资助国家：
日本
起止时间：
2006 至 2007
项目状态：
已结题

项目摘要

Investigation of the network structures constructed with antimony and indium oxides led to the synthesis of a new compound LiIn_2SbO_6. We measured the X-ray and neutron powder diffraction data, and determined its crystal structure by Rietveld analysis. The structure had no disorder and the space of the Li site was not so large as expected. On the other hand, when larger alkali metals like potassium were used instead of lithium, antimony-indium oxide networks of the hollandite-type structure with larger tunnels were formed. Furthermore, the antimony-oxide network of the hollandite-type could include not only indium but also transition elements. We were interested also in the pyrochlore structures with large cavities, and investigated ASbWO_6 systems (A: alkaline elements). If sodium was used as the alkaline element, a new form of NaSbWO_6 was formed though the compounds with the cubic pyrochlore structure and an orthorhombic structure had been reported. The Rietveld analysis of the powder X-ray data of the new form showed that the structure was similar to the orthorhombic LiSbWO_6 but had a new monoclinic structure slightly deformed from the orthorhombic structure. When lithium was used as the alkaline element, an oxide with a pyrochlore-like structure was obtained, and the structure was different from the reported one. These experimental results indicated that the network structures with antimony oxide systems constructed by the synthetic reactions were not confined only in those that were thermodynamically most stable. Therefore, if we could find suitable synthetic procedures, we could build a wide range of network structures with antimony oxide systems.

对锑和氧化铟构建的网络结构的研究导致合成了一种新化合物LiIn_2SbO_6。我们测量了X射线和中子粉末衍射数据，并通过Rietveld分析确定了其晶体结构。结构并无紊乱，李遗址的空间也没有想象中那么大。另一方面，当使用较大的碱金属（如钾）代替锂时，形成了具有较大孔道的钙锰矿型结构的锑-铟氧化物网络。此外，镁锰矿型的氧化锑网络不仅可以包含铟，还可以包含过渡元素。我们还对具有大空腔的烧绿石结构感兴趣，并研究了 ASbWO_6 系统（A：碱性元素）。如果使用钠作为碱性元素，虽然已经报道了具有立方烧绿石结构和斜方结构的化合物，但形成了新形式的NaSbWO_6。对新晶型的粉末X射线数据进行Rietveld分析表明，其结构与斜方晶系LiSbWO_6相似，但具有与斜方晶系结构略有变形的新单斜晶系结构。当使用锂作为碱性元素时，得到了具有类烧绿石结构的氧化物，且其结构与报道的不同。这些实验结果表明，通过合成反应构建的氧化锑体系的网络结构不仅限于热力学最稳定的网络结构。因此，如果我们能找到合适的合成方法，我们就可以用氧化锑系统构建广泛的网络结构。