title: Observation of divergent isotope effects as well as metal ion-modulated T(C) and spin-canting nature in isostructural supramolecular magnets.
abstract: The ion-pair complexes of [4-NH(2)-PyH][M(mnt)(2)] (M = Pt for 1 and Ni for 3) and their deuterated analogues [4-NH(2)-PyD][M(mnt)(2)] (M = Pt for 2 and Ni for 4) are isostructural with each other. Four complexes crystalline in monoclinic space group C2/c, whose asymmetric unit consists of two halves of [M(mnt)(2)](-) anions and one cation, show quite similar cell parameters and almost identical packing structures as well. In the crystals of 1-4, two types of crystallographically inequivalent [M(mnt)(2)](-) anions construct individual layers, which are separated by the cation layer; the supramolecular networks are formed via the H-bonding interactions between the [M(mnt)(2)](-) and 4-NH(2)-PyH(+) (or 4-NH(2)-PyD(+)) ions as well as the weakly ππ stacking interactions between the [M(mnt)(2)](-) anions. The four isostructural complexes exhibit canted antiferromagnetism, arising from the non-collinearity of the magnetic moments between the crystallographically inequivalent anion layers, with T(C) ≈ 14.8 K for 1, 13.6 K for 2, 7.7 K for 3 and 8.8 K for 4, respectively. Ac magnetic susceptibility measurements revealed that 1 and 2 show spin canting, while 3 and 4 show hidden-spin canting characteristics. The isostructural 1 and 3 were deuterated to give the divergent isotope effects on the cell volume and T(C).
authors.affiliation: State Key Laboratory of Materials-Oriented Chemical Engineering and College of Science, Nanjing University of Technology, Nanjing 210009, PR China.
authors.forename: Wen-Bo
authors.initials: WB
authors.lastname: Pei
authors.forename: Jian-Sheng
authors.initials: JS
authors.lastname: Wu
authors.forename: Xiao-Ming
authors.initials: XM
authors.lastname: Ren
authors.forename: Zheng-Fang
authors.initials: ZF
authors.lastname: Tian
authors.forename: Jingli
authors.initials: J
authors.lastname: Xie