Comparative study of two chemically isostructural polymers: [Cu2(VO2)(HPO4)2(NO3)(bpy)2].2H2O/H3PO4 (bpy is 2,2'-bipyridine).

Abstract

The title compounds, poly[bis(2,2'-bipyridine)bis(μ 3 -hydrogen phosphato)nitratodi-μ 2 -oxo-dicopper(II)vanadium dihydrate], [Cu2(V02)(HP04)2(N03)(C 10 H 8 N 2 ) 2 ].2H 2 O, (I), and poly[bis(2,2'-bipyridine)bis(μ 3 -hydrogen phosphato)nitratodi-μ 2 -oxo-dicopper(II)vanadium phosphoric acid solvate], [Cu2(VO 2 )(HP04)2(NO 3 )(C 10 H 8 N 2 ) 2 .H 3 PO 4 , (II), were obtained by similar hydrothermal methods but under different crystallization conditions. The trinuclear entity which serves as the basic unit in both structures presents two independent Cu II ions immersed in similar square-pyramidal N 2 O 3 environments plus an octahedral VO 6 core and is organized into a one-dimensional polymer, which is essentially identical in the two structures. The compounds are stabilized by different solvates, viz. two crystallization water molecules in (I) and a phosphoric acid molecule in (II), which provide the main structural differences through the diversity of interchain interactions in which they serve as bridges.