Abstract
The crystal structure of dichlorobis(dimethylsulfoxide-O)copper(II), [CuCl2(DMSO)(2)] (I), previously determined by Willett and Chang, is reinvestigated. It crystallizes in the orthorhombic system with the space group Pnma (NA degrees 62), Z = 4, and unit cell parameters a = 8.053(1) , b = 11.642(5) , c = 11.347(3) . Our structure determination is of a significantly higher precision in terms of bond lengths, angles, and R factors (e.g., Cu1-O1 = 1.9737(24) , O1-Cu1-O1(i) = 173.08(13)A degrees (symmetry code: (I) x, 1/2-y, z) and R(F (2)) = 0.046 compared to 1.955(4) , 173.0(3)A degrees and R(F) = 0.075). In contrast to the previous investigation, all H atoms are placed at calculated positions. In the title molecule, the Cu-II atom is five coordinated in a distorted square pyramidal geometry. Thus, as reported previously, it can be shown that the crystal structure consists of [CuCl2(DMSO)(2)] molecules which, by virtue of long Cu-Cl interactions, are tied together to form chains parallel to the [100] direction. The density functional theory (DFT) optimized structure at the B3LYP/6-311++G(2d,2p) level is compared with the experimentally determined molecular structure. The HOMO-LUMO energy gap and other related molecular properties are also calculated. Comprehensive experimental and theoretical structural studies on the studied complex are carried out by FT-IR and UV-visible spectroscopies.