摘要
Three dinuclear compounds of the types [Cu 2 (L) 2 (μ-tp)](ClO 4 /PF 6 ) 2 (1/2) and [Mn 2 (L) 2 (μ-tp)](ClO 4 ) 2 H 2 O (3) [L = N,N′-(bis-(pyridin-2-yl)benzylidene)-1,3- propanediamine and tp = terephthalate dianion] have been synthesized and characterized. Structures of 1-3 are solved using single crystal X-ray diffraction measurements. The structural analyses show bis(monodentate) in 1/2 and bis(bidentate) in 3 of terephthalate bridging motifs resulting dicationic dinuclear unit [M 2 (L) 2 (μ-tp)] 2+ [M = Cu (1/2) and Mn (3)]. Each metal center adopts distorted trigonal bipyramidal geometry in 1/2 and a distorted octahedral geometry in 3 with MN 4 O and MN 4 O 2 chromophores, respectively. Chelation by the tetradentate Schiff base along with bis(monodentate) and bis(bidentate) bridging of terephthalate complete pentacoordination around each copper(II) center in 1/2 and hexacoordination around each manganese(II) center in 3, respectively. Variable-temperature magnetic susceptibility measurements of 1-3 in the 2-300 K temperature range reveal weak antiferromagnetic interaction presumably due to long bridging arm. © 2013 Elsevier Ltd. All rights reserved.