Syntheses, structures and magnetic properties of two new metal complexes based on a pyridyl-diphosphonate ligand

Two new first-raw transition metal diphosphonate complexes, namely, {[Ni3([hpyedpH)2(H2O)4]·(H2O)2}n (1) and [Mn[hpyedpH2](H2O)]n (2), based on a multidentate ligand 1-hydroxy-2-(3-pyridyl)-ethylidene-1,1-diphosphonic acid (hpyedpH4) have been synthesized under hydrothermal reaction and structurally characterized by single-crystal X-ray diffraction, IR spectroscopy and element analyses. The data reveals that complex 1 is a 2D layer structure, whereas the complex 2 possesses a 1D motif. The powder X-ray diffraction (PXRD) patterns for complexes 1 and 2 were collected as well, which match well with the ones calculated from their single-crystal structure data. Magnetic measurements show that complex 1 is a ferrimagnet with Tc = 5.0 K. Magnetic studies of complex 2 indicate antiferromagnetic behavior.

Graphical abstractTwo new first-raw transition metal diphosphonate complexes, namely, {[Ni3([C5H5N-CH2C(OH)(PO3)2])2(H2O)4]·(H2O)2}n (1) and {Mn[C5H5N–CH2C–(OH)(PO3)(PO3H)](H2O)}n (2) have been synthesized. Magnetic measurements show that compound 1 is a ferrimagnet and compound 2 indicates antiferromagnetic behavior.Figure optionsDownload full-size imageDownload as PowerPoint slide