Synthesis and characterization of a new quasi-one-dimensional antiferromagnet CoF2(H2O)2(pyrazine)

A new one-dimensional (1D) antiferromagnetic transition metal hybrid fluoride CoF 2 (H 2 O) 2 (pyz) (pyz = pyrazine) together with two new isostructural MF 2 (H 2 O) 2 (pyz) (M = Ni 2+ , Zn 2+ ) have been successfully synthesized by the hydrothermal method. Their structures were determined by single crystal X-ray diffraction and they all crystallize in the same space group of C2/ m . The magnetic property of CoF 2 (H 2 O) 2 (pyz) 1 was measured and discussed. The Weiss constant of -20.6 K indicates dominant antiferromagnetic interaction and the effective magnetic moment of about 5.66 μ B suggests large unquenched orbital contribution and anisotropy in 1. The quantum fluctuations in the quasi-1D antiferromagnet of 1 prevent the appearance of long range magnetic order until 2.9 K, suggesting good 1D magnetism.