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Crystal structure of magnesium selenate hepta-hydrate, MgSeO4·7H2O, from neutron time-of-flight data.

ABSTRACT: MgSeO4·7H2O is isostructural with the analogous sulfate, MgSO4·7H2O, consisting of isolated [Mg(H2O)6](2+) octa-hedra and [SeO4](2-) tetra-hedra, linked by O-H?O hydrogen bonds, with a single inter-stitial lattice water mol-ecule. As in the sulfate, the [Mg(H2O)6](2+) coordination octa-hedron is elongated along one axis due to the tetra-hedral coordination of the two apical water mol-ecules; these have Mg-O distances of ?2.10?Å, whereas the remaining four trigonally coordinated water mol-ecules have Mg-O distances of ?2.05?Å. The mean Se-O bond length is 1.641?Å and is in excellent agreement with other selenates. The unit-cell volume of MgSeO4·7H2O at 10?K is 4.1% larger than that of the sulfate at 2?K, although this is not uniform; the greater part of the expansion is along the a axis of the crystal.

SUBMITTER: Fortes AD

PROVIDER: S-EPMC4186159 | biostudies-literature | 2014 Sep

REPOSITORIES: biostudies-literature

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Crystal structure of magnesium selenate hepta-hydrate, MgSeO4·7H2O, from neutron time-of-flight data.

Fortes A Dominic AD Gutmann Matthias J MJ

Acta crystallographica. Section E, Structure reports online 20140823 Pt 9

MgSeO4·7H2O is isostructural with the analogous sulfate, MgSO4·7H2O, consisting of isolated [Mg(H2O)6](2+) octa-hedra and [SeO4](2-) tetra-hedra, linked by O-H⋯O hydrogen bonds, with a single inter-stitial lattice water mol-ecule. As in the sulfate, the [Mg(H2O)6](2+) coordination octa-hedron is elongated along one axis due to the tetra-hedral coordination of the two apical water mol-ecules; these have Mg-O distances of ∼2.10 Å, whereas the remaining four trigonally coordinated water mol-ecules ...[more]

PMID: 25309161

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