Crystal structure of a CoII coordination polymer: catena-poly[[µ-aqua-bis-(µ-2-methyl-propano-ato)-κ2O:O';κ2O:O-cobalt(II)] monohydrate].

In the title cobalt(II) coordination polymer with isobutyrate ligands, {[Co{CH(CH3)2CO2}2(H2O)]·H2O} n , the Co2+ ion is hexa-coordinated in a slightly distorted octa-hedral coordination environment defined by two O atoms from two bridging water mol-ecules and four O atoms from four bridging carboxyl-ate ligands. The carboxyl-ates adopt two different coordination modes, µ-(κ2O:O') and µ-(κ2O:O), forming a one-dimensional polymeric chain extending along [010]. The intra-chain cobalt⋯cobalt separation is 3.2029 (2) Å. The polymeric chains are linked by hydrogen bonds involving the water mol-ecules of solvation, giving a two-dimensional network structure lying parallel to (100).