Coordination compounds of Hg₂²⁺: The crystal structure of Bis(acridine)dimercury(I) perchlorate

Abstract

Crystals of bis(acridine)dimercury(1) perchlorate, [Hg₂(C₁₃H₉N)₂] (ClO₄)₂ are monoclinic, a = 10.629(1), b = 16.841(2), c = 7.142(1) Å, β = 99.06(2)º, space group I2/m with Z = 2 dimeric formula units. The structure was solved from three-dimensional diffractometer X-ray data(1427 independent reflections), block-diagonal least-squares refinement of all atoms, including hydrogens, converging at R = 0.028. The mercury dimer, Hg-Hg 295177(5)Å, is coordinated in the axial positions by the acridine molecules, Hg-N 2.150(5) Å, the cation having C_2h symmetry.There are also two long contacts from each mercury atom to oxygen atoms of the perchlorate ions, Hg-0 2.958(6) Å. Evidence for a metal-ligand steric interaction is presented.