(IUCr) Crystallography Journals Online

[Contents scheme]

Acta Cryst. (2007). E63, m1911-m1912 [ doi:10.1107/S1600536807028772 ]

Heptaguanidinium sodium bis(pentaaquatetracosaoxoheptamolybdocobaltate) octahydrate

C.-B. Li

Abstract: The title compound, (CH₆N₃)₇Na[CoMo₇O₂₄(H₂O)₅]₂·8H₂O, features unusual [Co(H₂O)₅Mo₇O₂₄]^4- polymetallate anions. Two such anions are connected by a bridging octahedral sodium ion (Na site symmetry $\\overline{1}$ ) to form an {Na[(Co(H₂O)₅)(Mo₇O₂₄)]₂}^7- cluster. The Co-O and Mo-O distances are in the ranges 2.081 (11)-2.121 (10) and 1.701 (8)-2.508 (7) Å, respectively. Together with the cluster, the charge-balancing guanidinium cations (one of which is disordered about an inversion centre) and isolated water molecules form a three-dimensional supramolecular network by way of numerous O-HO and N-HO hydrogen bonds.

Online 15 June 2007