Spin canting and topological ferrimagnetism in two manganese(II) coordination polymers generated by in situ solvothermal ligand reactions

Two manganese(II) coordination polymers, [Mn2(bpt)(pa)2(N3)](n) [1; Hpa = picolinic acid, Hbpt = 3,5-bis(2-pyridyl)-4H-1,2,4-triazole] and [Mn-3(ina)2(pa)2(N3)2](n), (2; Hina = isonicotinic acid), have been synthesized by solvothermal treatment, in which the ligands bpt and pa were generated in situ by cyclocondensation and hydrolysis of 2-pyridylamidrazone, respectively. In 1, each binuclear subunit [Mn2(bpt)(N3)] bridged by bpt and N3 ligands is interlinked to four adjacent subunits via four tridentate pa ligands into a diamondoid 3D network, which shows spin-canting magnetism arising from the lack of inversion centers between the interacting spin centers. In 2, the Mn-II ions are alternately connected by double mu(1),(3)-carboxylate/mu(1,1)-azide and double mu(1,1)-carboxylate bridges into a 1D magnetic chain, which exhibits a topological ferrimagnetic behavior in an antiferromagnetic-antiferromagnetic-ferromagnetic sequence. These chains are further interlinked via ina ligands into a 2D network. ((C) Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007)