Kolitsch Uwe
Universität Wien, Institut für Mineralogie und Kristallographie, Geozentrum, Althanstrasse 14, A-1090 Wien, Austria.
Acta Crystallogr C. 2006 May;62(Pt 5):i35-7. doi: 10.1107/S0108270106012996. Epub 2006 Apr 29.
Sodium indium(III) chromate(VI) dihydrate, NaIn(CrO4)2.2H2O, synthesized from an aqueous solution at room temperature, is the first indium(III) member of the large family of compounds with kröhnkite [Na2Cu(II)(S(VI)O4)2.2H2O]-type chains. The crystal structure is based on infinite octahedral-tetrahedral [In(CrO4)2(H2O)2]- chains along [010], linked via charge-balancing Na+ cations. The slightly distorted InO4(H2O)2 octahedra are characterized by a mean In-O distance of 2.125 A. The CrO4 tetrahedra are strongly distorted (mean Cr-O = 1.641 A). The Na atom shows an octahedral coordination, unprecedented among compounds with kröhnkite-type chains. The NaO6 octahedra share opposite edges with the InO4(H2O)2 octahedra to form infinite [001] chains. The hydrogen bonds are of medium strength. NaIn(CrO4)2.2H2O belongs to the structural type F2 in the classification of Fleck, Kolitsch & Hertweck [Z. Kristallogr. (2002), 217, 435-443], and is isotypic with KAl(CrO4)2.2H2O and MFe(CrO4)(2).2H2O (M = K, Tl or NH4). All atoms are in special positions except one O atom.
铬酸铟（III）钠（VI）二水合物，NaIn（CrO₄）₂·2H₂O，在室温下由水溶液合成，是具有板铅铀矿型[Na₂Cu（II）（S（VI）O₄）₂·2H₂O]链的化合物大家族中的首个铟（III）成员。晶体结构基于沿[010]方向的无限八面体 - 四面体[In（CrO₄）₂（H₂O）₂]链，通过电荷平衡的Na⁺阳离子相连。略微扭曲的InO₄（H₂O）₂八面体的平均In - O距离为2.125 Å。CrO₄四面体严重扭曲（平均Cr - O = 1.641 Å）。Na原子呈现八面体配位，这在具有板铅铀矿型链的化合物中是前所未有的。NaO₆八面体与InO₄（H₂O）₂八面体共享相对的边以形成无限的[001]链。氢键具有中等强度。NaIn（CrO₄）₂·2H₂O属于Fleck、Kolitsch和Hertweck分类中的结构类型F2 [《晶体学报》（2002年），217，435 - 443]，并且与KAl（CrO₄）₂·2H₂O和MFe（CrO₄）₂·2H₂O（M = K、Tl或NH₄）同型。除了一个O原子外，所有原子都处于特殊位置。
