A novel method for synthesizing crystalline copper carbodiimide, CuNCN. Structure determination by X-ray rietveld refinement

作者：Liu XH; Wankeu MA; Lucken H; Dronskowski R^*

来源：Zeitschrift Fur Naturforschung Section B-a Journal of Chemical Sciences, 2005, 60(6): 593-596.

DOI：10.1515/znb-2005-0601

• copper
• cyanamide
• carbodiimide
• rietveld refinement
• Jahn-Teller distortion

Well-crystallized copper carbodiimide, CuNCN, was synthesized by the slow oxidation of a copper(l) cyanamide precursor under aqueous conditions. The X-ray powder data evidence the orthorhombic system and space group Cmcm with a = 2.9921(1), b = 6.1782(1), c = 9.4003(2) angstrom, V = 173.769(5) angstrom(3) and Z = 4. There is a strongly distorted octahedral Cu2+ coordination reflecting a typical first-order Jahn-Teller effect, with interatomic distances of 4 x Cu-N = 2.001(2) angstrom and 2 x Cu-N = 2.613(3) angstrom; the NCN2- unit adopts the carbodiimide shape with C-N = 1.227(4) A. Despite the formal d(9) electron count of Cu2+, CuNCN exhibits a small temperature-independent paramagnetism and is likely to be a metallic conductor.

• 出版日期2005-6