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Garnet-type Mn(3)Cr(2)(GeO(4))(3).

ABSTRACT: Single crystals of garnet-type trimanganese(II) dichrom-i-um(III) tris-[orthogermanate(IV)], Mn(II) (3)Cr(III) (2)(GeO(4))(3), were obtained by utilizing a chemical transport reaction. Corres-ponding to the mineral garnet with the general formula A(II) (3)B(III) (2)(SiO(4))(3), each of the four elements occupies only one crystallographically distinct position. Mn(2+) occupies the respective A position (Wyckoff site 24c, site symmetry 2.22), being surrounded by eight O atoms that form a distorted cube [d(Mn-O) = 2.291?(2) and 2.422?(2)?Å, 4× each], while Cr(3+) on the B position (Wyckoff site 16a, site symmetry .-3.) is situated in a slightly distorted octa-hedron of six O(2-) anions [d(Cr-O) = 1.972?(2)?Å, 6×]. In addition, the O atoms on general site 96h form isolated [GeO(4)](4-) tetra-hedra with Ge(4+) on site 24d [site symmetry -4..; d(Ge-O) = 1.744?(2)?Å, 4×].

SUBMITTER: Lipp C

PROVIDER: S-EPMC3344288 | biostudies-literature | 2012 May

REPOSITORIES: biostudies-literature

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Garnet-type Mn(3)Cr(2)(GeO(4))(3).

Lipp Christian C Strobel Sabine S Lissner Falk F Niewa Rainer R

Acta crystallographica. Section E, Structure reports online 20120421 Pt 5

Single crystals of garnet-type trimanganese(II) dichrom-i-um(III) tris-[orthogermanate(IV)], Mn(II) (3)Cr(III) (2)(GeO(4))(3), were obtained by utilizing a chemical transport reaction. Corres-ponding to the mineral garnet with the general formula A(II) (3)B(III) (2)(SiO(4))(3), each of the four elements occupies only one crystallographically distinct position. Mn(2+) occupies the respective A position (Wyckoff site 24c, site symmetry 2.22), being surrounded by eight O atoms that form a distorted ...[more]

PMID: 22590054

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