Crystal structure oftrans-bis(ethane-1,2-diamine-κ2N,N′)bis(thiocyanato-κN)chromium(III) perchlorate from synchrotron data

Abstract

The structure of the title compound, [Cr(NCS)2(C2H8N2)2]ClO4, has been determined from synchroton data. The asymmetric unit consists of one half of a centrosymmetric CrIIIcomplex cation and half of a perchlorate anion with the Cl atom on a twofold rotation axis. The CrIIIion is coordinated by the four N atoms of two ethane-1,2-diamine (en) ligands in the equatorial plane and two N-bound thiocyanate (NCS−) anions in atrans-axial arrangement, displaying a slightly distorted octahedral geometry with crystallographic inversion symmetry. The Cr—N(en) bond lengths are in the range 2.053 (16)–2.09 (2) Å, while the Cr—N(thiocyanate) bond length is 1.983 (2) Å. The five-membered en rings are disordered over two sites, with occupancy ratios of 0.522 (16):0.478 (16). Each ClO4−anion is disordered over two sites with equal occupancy. The crystal structure is stabilized by intermolecular hydrogen bonds involving the en NH2groups as donors and perchlorate O and thiocyanate S atoms as acceptors.