КРИСТАЛЛОХИМИЯ СЕЛЕНАТОВ С МИНЕРАЛОПОДОБНЫМИ СТРУКТУРАМИ. II. КРИСТАЛЛИ ЧЕСКАЯ СТРУКТУРА [AL(H20)6](SE04)(N03)(H20) И ЕЕ РОДСТВО СО СТРУКТУРАМИ АЛУНОГЕНА

Abstract

Crystal structure of a new compound [Al(H20)6](Se04)(N03)(H20) (triclinic, space group P\,a = 6.159(3), b = 7.774(4), с = 12.326(5) A, a = 90.43(4), 0 = 102.32(4), у = 96.63(4)°, V = 572.4(5) A3) has been solved by direct methods and refined to R\ = 0.041 for 2031 unique observed reflections with \Fkti\ > 4o\Fhki\- The basis of the structure is a layer of the [A13+(H20)6]3+ octahedra and (Se04)2~ tetrahedra linked via hydrogen bonds. The layers are parallel to (001) and are at the z ~ 0 and z ~ levels. The interlayer contains nitrate groups (their planes are perpendicular to the [100] direction) and H2014 water molecules. Analysis of the composition and structure of the alumoselenate layers shows their identity to the layers of coordination polyhedra observed in the structures of alunogen and its selenate analogue. The general formula of these compounds can be written as {[A1(H20)6](T04)}2X, where X = (S04)(H20)5 for alunogen, X = (Se04)(H20)4 for [Al(H20)6]2(Se04)3(H20)4 and X = (N03)2(H20)2 for [Al(H20)6](Se04)(N03)(H20).