Heteropolynuclear Metamagnet Showing Spin Canting and Single-Crystal to Single-Crystal Phase Transformation

The two-dimensional heteropolynuclear metal-organic framework [Co3Zn2(m-BDC)4(μ3-OH)2(μ2-OH2)2(H2O)4]·4.5H2O (1) (m-H2BDC = 1,3-benzenedicarboxylic acid) has been hydrothermally synthesized and characterized by single-crystal X-ray diffraction, infrared spectrum, X-ray powder diffraction, and elemental analysis. Our experimental results signify that the formation of compound 1 is highly medium-selective and temperature-sensitive in the hydrothermal system. Interestingly, 1 undergoes a single-crystal to single-crystal structural phase transition from orthorhombic Pmna to monoclinic P21/c (1‘) at very low temperature of about 156.5 K. In this process, we found two topologically different water tapes. More importantly, the magnetic property of the target compound was also intensively investigated in the temperature range of 2−300 K and shows the coexistence of spin canting and field-induced metamagnetism.