Synthesis and Structure of A Carboxyl-Bridged Heteronuclear Copper-Terbium Complex: [CuTb(CH 2 C(CH 3 )COO) 5 (PHEN)(H 2 O)] 2.

The title complex has prepared by the reaction of TbL 3 , Cu(NO 3 ) 2 and phen in H 2 O/EtOH (where L = α-methylacrylato; phen = 1,10-phenanthroline) and its structure determined by X-ray diffraction methods. The complex crystallizes in the triclinic space group P ī with Z = 1, a = 11.569(2), b = 14.584(3), c = 11.479(2) Å, α = 101.03(2), β = 104.37(2), γ = 74.01(1)°, and the structure was refined to R = 0.041 for 6463 observed reflections. The structure contains a discrete tetranuclear CuTbTbCu molecule. Copper(II) and terbium(III) are bridged by three bidentate carboxyl groups with a Tb ··· Cu separation of 3.9059(9) Å. The Tb ion is eight coordinate and exhibits a distorted square antiprism. The Cu ion is five coordinate and has distorted pyramidal geometry. [ABSTRACT FROM AUTHOR]