Magneto-structural Correlations in Ni-Halide···Halide-Ni Chains.

We present the magnetic properties of a new family of = 1 molecule-based magnets, NiF(3,5-lut)·2HO and NiX(3,5-lut), where X = HF, Cl, Br, or I (lut = lutidine CHN). Upon creation of isolated Ni-X···X-Ni and Ni-F-H-F···F-H-F-Ni chains separated by bulky and nonbridging lutidine ligands, the effect that halogen substitution has on the magnetic properties of transition-metal-ion complexes can be investigated directly and in isolation from competing processes such as Jahn-Teller distortions. We find that substitution of the larger halide ions turns on increasingly strong antiferromagnetic interactions between adjacent Ni ions via a novel through-space two-halide exchange.

Controlling Magnetic Anisotropy in a Zero-Dimensional = 1 Magnet Using Isotropic Cation Substitution.

The [ZnNi(HF)(pyz)]SbF ( = 0.2; pyz = pyrazine) solid solution exhibits a zero-field splitting () that is 22% larger [ = 16.2(2) K (11.