LAUSR

Abstract Single crystals of new high symmetrical borophosphate, Ba8{Ni2+0.7Mn2+0.2Fe3+0.014⎕0.086}4⋅[BP3O10.9(OH)2.1]4, sp.gr. Fd 3 ¯ c, a = 25.36 A, are synthesized in multi-component hydrothermal systems. It is large inorganic structure with the anionic part, characterized as a complex unit of four-octahedra-cluster {Ni,Mn}4 surrounded by four borophosphate groups [BP3O10.9(OH)2.1]4 with the statistical orientation of BO4- and PO4-tetrahedra. Being in the “solution” of numerous Ba2+ ions, units are isolated from each other. Similar octahedral clusters are in K4{Ge4+0.85I5+0.12⎕0.03}4Ge5O20, K(H3O)3{Ge}4O4[GeO4]3 and Ba-pharmacosiderite Ba0.5{Fe3+4}(OH)4[AsO4]3⋅6.16H2O. New original borophosphate has narrow channels, open along coordinate axes, which are formed by spirals of Ba-cations formed by 41 and 43 axes. The structure may be assigned to the new division - “anti-zeolite” with a positively charged framework formed by prevailing large cations with voids filled by anionic units. Yellowish-red color of crystals is investigated in details by optical spectroscopy, showing that namely Ni2+ions are responsible for that.