LAUSR

Abstract Hydrothermal reactions of copper(II) and cobalt(II) salts with 1-tetrazole-phenyl-4-methylphosphonic acid yielded the coordination polymers [Cu(H 2 O)(HO 3 PCH 2 C 6 H 4 CN 4 )]·H 2 O ( 1 ·H 2 O) and [Co(H 2 O) 2 (HO 3 PCH 2 C 6 H 4 CN 4 H) 2 ]·2H 2 O ( 2 ·2H 2 O). Compound 1 ·H 2 O is two dimensional and is constructed from chains of trans -corner sharing, ‘4+2’ axially distorted {CuO 4 N 2 } octahedra. These chains are linked through the organic tethers of the ligands in the doubly deprotonated form{HO 3 PCH 2 C 6 H 4 CN 4 } 2− to propagate in two-dimensions. In contrast, compound 2 ·2H 2 O is one-dimensional and features {CoO 4 N 2 } octahedra linked through pairs of ligands in the singly deprotonated form {HO 3 PCH 2 C 6 H 4 CN 4 H} −1 , i.e. with the tetrazole terminus in the neutral form. The magnetic properties of compound 1 ·H 2 O reflect the structure where the Cu(II) ions are bridged by syn-syn phosphate and tetrazolate Cu-N-N-Cu bridges, with the former linkage likely to transfer ferromagnetic coupling whereas the latter leads to antiferromagnetic coupling. The two competing pathways lead to negligible overall coupling.