Unprecedented Mn(II) - Phosphate 3D Coordination Polymer with Novel pkb1 Topological Network Showing Spin-Canted Antiferromagnetism

Abstract

A novel Mn(II)phosphate coordination polymer, {Mn2.5(HPO4PO4)H2O)2}n, has been synthesized under solvothermal conditions. This is the first phosphate-based Mn(II) complex, which is obtained in excellent yield without using any external organic amine as a structure directing agent. The complex has a 3D non-interpenetrated unprecedented 5-nodal (5,5,6,6,7)-connected pkb1 topological network. It has been characterized by single-crystal X-ray diffraction, IR spectroscopy, elemental analysis (CHN analyzer and energy-dispersive X-ray spectroscopy), and thermogravimetry. Variable temperature magnetic susceptibility measurements indicate that the complex exhibits spin-canted antiferromagnetic behaviour at low temperature. The electron paramagnetic resonance measurements, at ambient and at low temperature, of the complex are also consistent with magnetic behaviour.