Exploration of the structural features and magnetic behaviour in a novel 3-dimensional interpenetrating Co(II)-based framework / created by Soumyabrata Goswami, A. Mondal, Sanjit Konar

A new Co(II)-based three-dimensional (3D) framework having the molecular formula [Co(C4O4)(4-bpmh))H2O)2]n·2nH2O·2nMeOH·(1) (4-bpmh=N, N-bis-pyridin-4-ylmethylene-hydrazine) has been syn-thesized using a mixed ligand system and characterized by elemental analysis, IR spectroscopy, thermogravi-metric analysis, single crystal X-ray diffraction and variable temperature magnetic study. The framework isconstructed by the bridging squarate (C4O2−4)and N, N-bis-pyridin-4-ylmethylene-hydrazine (4-bpmh) ligandsand interpenetration of the 2D grid-like frameworks at definite angles gives rise to 2D→3D inclined polycate-nation with sql/Shubnikov tetragonal plane net topology. Extensive non-covalent interactions (H-bonding aswell asπ···πinteractions) are also observed which stabilises the 3D arrangement. Additionally, complex1contains 1D channels of large dimensions (10.91×11.78 Å2)that runs along theb-axis. Variable temperatureDC magnetic susceptibility study reveals dominant spin–orbit coupling effect typical of the4T1gground stateof octahedral high-spin Co(II) ion at a higher temperature range.