catena-Poly[[tetra-3-isonicotinato-3-oxalato-2-oxalato-disamarium(III)disilver(I)] dihydrate]

Acta Crystallographica Section E

Structure Reports Online

Volume 66, Part 1 (January 2010)

metal-organic compounds

Acta Cryst. (2010). E66, m88-m89 [ doi:10.1107/S1600536809054208 ]

catena-Poly[[tetra-₃-isonicotinato-₃-oxalato-₂-oxalato-disamarium(III)disilver(I)] dihydrate]

Z. Li and S. Yue

Abstract: In the title compound, {[AgSm(C₆H₄NO₂)₂(C₂O₄)]·H₂O}_n, the asymmetric unit contains one Sm^III ion, one Ag^I ion, two unique isonicotinate (ina) ligands, two half oxalate (ox) ligands (one on an inversion centre, the other on a twofold axis) and one uncoordinated water molecule. The central Sm^III ion is nine-coordinated by four O-donor atoms from separate bidentate bridging ox ligands and five O-donor atoms from the two ina ligands (both bidentate) and a symmetry-related ina ligand [Sm-O = 2.389 (4)-2.791 (4) Å], giving a distorted monocapped square antiprismatic geometry. The Ag^I ion is three-coordinated in a T-shaped geometry involving two ina N-donor atoms [Ag-N = 2.181 (6) and 2.185 (5) Å] and a bridging oxalate O-donor atom [Ag-O = 2.620 (4) Å]. The three-dimensional heterometallic Sm-Ag coordination polymer, having a unique (3,4,6)-connected five-nodal net topology, is constructed from two-dimensional samarium-oxalate layers and pillared Ag(ina)₂ subunits. Intermolecular water-carboxylate O-HO hydrogen-bonding interactions are also present.