Crystal structure of hexakis(pyridine 1-oxide)mercury(II) bisperchlorate

Abstract

The crystal structure of the title compound has been determined by single-crystal X-ray diffraction by use of conventional heavy-atom methods. The structure was refined by a block-diagonal least-squares procedure to R 0·08 for 345 independent visually estimated reflections. Crystals are rhombohedral, space group R, a= 9·77 ± 0·01 Å, α= 80·7 ± 0·1°(hexagonal cell: a= 12·64, c= 19·47 Å), Z= 1.

The structure consists of cubic close-packed layers of [Hg(C₅H₅NO)₆]²⁺ cations with the ClO₄^– ions in ‘trigonal holes’ of the array. The mercury has regular octahedral co-ordination, d(Hg–O) 2·35 Å. Distances and angles within the ligand and the perchlorate ion are as expected. The i.r. spectrum of the perchlorate ion shows band-splitting consistent with its C_3v symmetry.