Hydrothermal synthesis, structural characterisation and magnetic behaviour of (4,4′-bpyH)2[M(4,4′-bpy)(H2O)4][V2O2(pmida)2] · 2H2O (M = Mn2+ and Co2+)

Two new structures containing N-(phosphonomethyl)iminodiacetate residues (pmida4−) and 4,4′-bipyridine, (4,4′-bpyH)2[M(4,4′- bpy)(H2O)4][V2O2(pmida)2] · 2H2O (where M = Mn2+ or Co2+), have been synthesised using hydrothermal methods and characterised structurally by single-crystal and powder X-ray diffraction, elemental analysis, infrared spectroscopy and thermal analysis. The magnetic behaviour of these two materials is also described. The compounds are formed by close packing (mediated by electrostatic interactions) of one-dimensional [M(4,4′-bpy)(H2O)4]n2n+ cationic polymers and 4,4′-bpyH+ cations, along with dimeric centrosymmetric [V2O2(pmida)2]4− anionic moieties. Hydrogen-bonded sub-network formed by highly directional and very strong homonuclear O–H⋯O and heteronuclear N+–H⋯O interactions interconnects these moieties into a three-dimensional framework. Systematic surveys of the Cambridge Structural Database were performed to collect information on the distribution of bond distances (Mn–N, Mn–Owater, Co–N, Co–Owater, V–N, V–Ocarboxylate and VO), and to characterise the local coordination environments of Mn2+, Co2+ and V4+.

Graphical abstractThe compounds (4,4′-bpyH)2[M(4,4′- bpy)(H2O)4][V2O2(pmida)2] · 2H2O (M = Mn2+ and Co2+), containing N-(phosphonomethyl)iminodiacetate residues (pmida4−), have been synthesised using hydrothermal methods and structurally characterised.Figure optionsDownload full-size imageDownload as PowerPoint slide