Crystal structure of tin(IV) chloride octahydrate

Abstract

The title compound was crystallized according to the solid–liquid phase diagram at lower temperatures. It is built-up of SnCl4(H2O)2 octa­hedral units and lattice water mol­ecules. An intricate three-dimensional network of O—H⋯O and O—H⋯Cl hydrogen bonds between the complex molecules and the lattice water molecules is formed in the crystal structure.

Crystal structure of magnesium dichloride decahydrate determined by X-ray and neutron diffraction under high pressure

“…The water molecules in the Mg(D 2 O) 6 octahedron are connected to ten water molecules and six Cl À anions via hydrogen bonds (Fig. 5) and these are interpreted as the second hydration shell, as described for n = 8 and 12 by Hennings et al (2013). Interestingly, MgCl 2 Á10D 2 O presents two bifurcated hydrogen bonds (O2-D4Á Á ÁCl1/ Á Á ÁCl1 and O4-D6Á Á ÁO2/Á Á ÁO2, see Fig.…”

“…These were postulated on the basis of chemical analyses many years ago (Panfilowa, 1894;Getman, 1935), although their existence has been questioned in the recent literature (Hennings et al, 2013). Hennings et al (2013) concluded that the highest hydration number for both magnesium bromide and magnesium iodide is 9 based on their crystallization experiments. Because compounds with larger ionic radii frequently form analogs for high-pressure phases of compounds with smaller ionic radii such as GeO 2 and SiO 2 , it would not be surprising if MgBr 2 and/or MgI 2 decahydrates are isomorphous to MgCl 2 decahydrate and exhibit stability or metastability at atmospheric pressure.…”

“…4-6 were drawn using the VESTA program (Momma & Izumi, 2011). The structure of MgCl 2 Á10D 2 O comprises Mg(D 2 O) 6 octahedra, similar to other water-rich magnesium dichloride hydrates (n = 6; Agron & Busing, 1985, or n = 8, 12;Hennings et al, 2013). These octahedra display a hexagonal close-packed arrangement in the ab plane and stack along the c * direction following an ABCABC sequence ( Figs.…”

“…The discovery of decahydrate in magnesium dichloride hydrates may imply the existence of decahydrates in magnesium bromide and magnesium iodide. These were postulated on the basis of chemical analyses many years ago (Panfilowa, 1894;Getman, 1935), although their existence has been questioned in the recent literature (Hennings et al, 2013). Hennings et al (2013) concluded that the highest hydration number for both magnesium bromide and magnesium iodide is 9 based on their crystallization experiments.…”

“…Magnesium dichloride hydrates (MgCl 2 ÁnH 2 O) exhibit a number of different hydrate phases, with n = 1, 2, 4, 6, 8 and 12, at atmospheric pressure. Although the crystal structures of bischofite (n = 6) and magnesium dichloride dodecahydrate (n = 12) have been known from a long time (n = 6; Andress & Gundermann, 1934, n = 12;Sasvá ri & Jeffrey, 1966), and even H-atom positions are well determined for n = 6 using singlecrystal neutron diffraction (Agron & Busing, 1985), the structures of other magnesium dichloride hydrates including H-atom parameters have only been recently investigated (n = 1, 2; Sugimoto et al, 2007, n = 4;Schmidt et al, 2012, n = 8, 12;Hennings et al, 2013). Interestingly, except for n = 1, all n values in these hydrates are even, and more curiously n = 10 has never been reported.…”