Synthesis, crystal structure and magnetic behaviour of dimeric and polymeric gadolinium carboxylates with pentafluoropropionic acid

摘要

The three novel gadolinium(III) containing compounds (NH3CH3)[Gd(CF3CF2COO)(4)(H2O)] (1), (NH3C2H5)[Gd(CF3CF2COO)(4)(H2O)] (2) and ((CH3)(4)N)[Gd(CF3CF2COO)(3)(H2O)(2)]CF3CF2COO (3) were synthesized and structurally characterized by X-ray crystallography. In the crystal structures of 1 and 2, the gadolinium ions are bridged by carboxylate groups to dimers with a Gd3+-Gd3-,distance of 451.6(2) (1) and 451.8(3) pm (2), respectively. In the crystal structure of 3 the Gd3+ ions are bridged by carboxylate groups to chains with almost the same Gd3+-Gd3+ distances (494.0(8) and 503.4(7) pm). The magnetic behaviour of 1 and 2 was investigated in the temperature range of 1.76-300 K. The magnetic data indicate weak antiferromagnetic interactions within the dimeric unit. (c) 2006 Elsevier B.V. All rights reserved.