Redetermination of despujolsite, Ca3Mn4+(SO4)2(OH)6·3H2O
نویسندگان
چکیده
The crystal structure of despujolsite [tricalcium manganese bis-(sulfate) hexahydroxide tri-hydrate], the Ca/Mn member of the fleischerite group, ideally Ca(3)Mn(4+)(SO(4))(2)(OH)(6)·3H(2)O, was previously determined based on X-ray diffraction intensity data from photographs, without H-atom positions located [Gaudefroy et al. (1968 ▶). Bull. Soc. Fr. Minéral. Crystallogr.91, 43-50]. The current study redetermines the structure of despujolsite from a natural specimen, with all H atoms located and with higher precision. The structure of despujolsite is characterized by layers of CaO(8) polyhedra (m.. symmetry) inter-connected by Mn(OH)(6) octa-hedra (32. symmetry) and SO(4) tetra-hedra (3.. symmetry) along [001]. The average Ca-O, Mn-O and S-O bond lengths are 2.489, 1.915, and 1.472 Å, respectively. There are two distinct hydrogen bonds that stabilize the structural set-up. This work represents the first description of hydrogen bonds in the fleischerite group of minerals.
منابع مشابه
Schaurteite, Ca3Ge(SO4)2(OH)6·3H2O
This report presents the first crystal structure determination of the mineral schaurteite, ideally Ca(3)Ge(SO(4))(2)(OH)(6)·3H(2)O, tricalcium germanium bis-(sulfate) hexa-hydroxide trihydrate. This single-crystal X-ray diffraction study investigated a natural sample from the type locality at Tsumeb, Namibia. Schaurteite is a member of the fleischerite group of minerals, which also includes fle...
متن کاملThe crystal chemistry of four thorium sulfates
Four thorium sulfate compounds have been synthesized and characterized. [Th(SO4)2(H2O)7] 2H2O (ThS1) crystallizes in space group P21/m, a1⁄47.2488(4), b1⁄412.1798(7), c1⁄48.0625(5) Å, b1⁄498.245(1); Na10[Th2(SO4)9(H2O)2] 3H2O (ThS2), Pna21, a1⁄417.842(2), b1⁄46.9317(8), c1⁄427.550(3) Å; Na2[Th2(SO4)5 (H2O)3] H2O (ThS3), C2/c, a1⁄416.639(2), b1⁄49.081(1), c1⁄425.078(3) Å, b1⁄4 95.322(2); [Th4(SO...
متن کاملContribution to the mineralogy of acid drainage of Uranium minerals: Marecottite and the zippeite-group
Sulfate-rich acid waters produced by oxidation of sulfide minerals enhance U mobility around U ores and U-bearing radioactive waste. Upon evaporation, several secondary uranyl minerals, including many uranyl sulfates, precipitate from these waters. The zippeite-group of minerals is one of the most common and diverse in such settings. To decipher the nature and crystal chemistry of the zippeite-...
متن کاملRedetermination of kovdorskite, Mg2PO4(OH)·3H2O
The crystal structure of kovdorskite, ideally Mg(2)PO(4)(OH)·3H(2)O (dimagnesium phosphate hydroxide trihydrate), was reported previously with isotropic displacement paramaters only and without H-atom positions [Ovchinnikov et al. (1980 ▶). Dokl. Akad. Nauk SSSR.255, 351-354]. In this study, the kovdorskite structure is redetermined based on single-crystal X-ray diffraction data from a sample f...
متن کاملAgardite-(Y), Cu2+ 6Y(AsO4)3(OH)6·3H2O
Agardite-(Y), with a refined formula of Cu(2+) 5.70(Y0.69Ca0.31)[(As0.83P0.17)O4]3(OH)6·3H2O [ideally Cu(2+) 6Y(AsO4)3(OH)6·3H2O, hexa-copper(II) yttrium tris-(arsenate) hexa-hydroxide trihydrate], belongs to the mixite mineral group which is characterized by the general formula Cu(2+) 6 A(TO4)3(OH)6·3H2O, where nine-coordinated cations in the A-site include rare earth elements along with Al, C...
متن کامل