title: Metal monophosphonates M{(2-C5H4NO)CH2PO3}(H2O)2 (M = Co, Ni, Mn, Cd): synthesis, structure, and magnetism.
abstract: Four isostructural metal monophosphonates, M{(2-C(5)H(4)NO)CH(2)PO(3)}(H(2)O)(2) with M = Co (1), Ni (2), Mn (3), and Cd (4), were synthesized and structurally characterized. These compounds show a double-chain structure in which the M(2)(μ-O)(2) dimers are connected by O-P-O bridges. The magnetic responses of 1-3 were investigated over a wide range of magnetic fields (up to 10 T) and temperatures (down to 50 mK). Except for 4, which is weakly diamagnetic from 2 K to room temperature, the dominant magnetic interactions are antiferromagnetic. Isothermal magnetic field sweeps at 50 mK provide signatures in the magnetic responses that are associated with antiferromagnetic to field-induced fully polarized (magnetically saturated) transitions. Analysis of the magnetic data indicates that 1 and 2 form magnetic dimer-like clusters with weak dimer-dimer interactions present. Contrastingly, the magnetic interactions present in 3 are significantly weaker, so a definitive description of the magnetism of this compound is elusive.
authors.affiliation: State Key Laboratory of Coordination Chemistry, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210093, People's Republic of China.
authors.forename: Ting-Hai
authors.initials: TH
authors.lastname: Yang
authors.forename: Elisabeth S
authors.initials: ES
authors.lastname: Knowles
authors.forename: Daniel M
authors.initials: DM
authors.lastname: Pajerowski
authors.forename: Jian-Sheng
authors.initials: JS
authors.lastname: Xia
authors.forename: Liang
authors.initials: L
authors.lastname: Yin
authors.forename: Song
authors.initials: S
authors.lastname: Gao
authors.forename: Mark W
authors.initials: MW
authors.lastname: Meisel
authors.forename: Li-Min
authors.initials: LM
authors.lastname: Zheng