摘要

A novel homodinuclear complex [(tacn)Cr(mu-OH)(2)(mu-CO3)Cr(tacn)](CIO4)(2).3H(2)O (tacn = 1,4,7-triazacyclononane) has been synthesized and characterized by single-crystal X-ray diffraction analysis. The complex crystallizes in space group Anna, with a = 14.323(2), b = 21.958(3), c = 9.0092(14) Angstrom, Z = 4, R-1 = 0.0552, wR(2) = 0. 1222. The structure consists of the binuclear cation [(tacn)Cr(mu-OH)(2)(mu-CO3)Cr(tacn)](2+), uncoordinated perchlorate anions and lattice water molecules. Metal centres are linked together by two hydroxo bridges and one carbonato bridge and there are intramolecular Cr-Cr interactions. The geometry around each chromium(III) ion is distorted octahedral. Hydrogen atoms of two neighbouring 1,4,7-triazacyclononane ligands connect with the uncoordinated oxygen atom of the carbonato group through hydrogen bonds to form a 1-D chain. Measurements of variable-temperature (2-300 K) magnetic susceptibilities show an anti-ferromagnetic interaction between Cr(III) ions.