摘要 : Two polymorphs Ni(II) complexes {[Ni(meso-CTH)(mu(1.5)-dca)]ClO4}(n) (1) and [Ni(meso-CTH)][Ni(meso-CTH)(dca)(2)](ClO4)(2) (2) have been obtained in the same synthesis from dicyanamide (dca) and [Ni(meso-CTH)](ClO4)(2) and have be... 展开 Two polymorphs Ni(II) complexes {[Ni(meso-CTH)(mu(1.5)-dca)]ClO4}(n) (1) and [Ni(meso-CTH)][Ni(meso-CTH)(dca)(2)](ClO4)(2) (2) have been obtained in the same synthesis from dicyanamide (dca) and [Ni(meso-CTH)](ClO4)(2) and have been characterized by X-ray crystallography and magnetic measurements. Complex I is a ID cationic polymeric zig-zag chain with single end-to-end dca bridges connecting Ni(II) ions in trans positions, whereas in Compound 2 coexist two different types of Ni(H) mononuclear units. cationic square-planar and neutral octahedral. Variable-temperature magnetic measurements reveal weak ferromagnetic interactions across the single end-to-end dca bridges in 1. while for 2 the magnetic behaviour agrees with that expected for isolated octahedral Ni(II) ions with a significant zero-field splitting. (C) 2004 Elsevier B.V. All rights reserved. [References: 36] 收起