Poly[[aquabis(μ₃-isonicotinato-κ³O:O′:N)tris(μ₂-isonicotinato-κ³O,O′:N)(nitrato-κO)bis(μ₄-oxalato-κ⁶O¹,O²:O²:O^1′,O^2′:O^1′)dierbium(III)tetrasilver(I)] tetrahydrate]

Abstract

In the title coordination polymer, {[Ag 4 Er 2 (C 6 H 4 NO 2 ) 5 (C 2 O 4 ) 2 (NO 3 )(H 2 O)]·4H 2 O} n , each Er III atom is coordinated in a bicapped trigonal–prismatic coordination geometry by three O atoms from two isonicotinate (IN) ligands, four O atoms from two oxalate ligands and one O atom from either a nitrate ion or a water molecule, both of which are half-occupied over the same site. One Ag I atom has a Y-shaped geometry defined by one N atom from one IN ligand, one O atom from another IN ligand and one O atom from an oxalate ligand. The other Ag I atom is coordinated by two IN ligands and one O atom from an oxalate ligand. One of the IN ligands is disordered over an inversion center and forms a bridge between two centrosymmetric Ag I ions. Due to the disorder, this IN ligand coordinates to the Ag atom through either the pyridyl N or the carboxylate O atoms. The IN and oxalate ligands link the Er and Ag atoms into a three-dimensional coordination framework. O—H...O and C—H...O hydrogen bonds are observed in the crystal structure.