Crystal structure and vibrational spectroscopy of hexa-amminechromium(III) pentachloromercurate(II)

Abstract

Crystals of the title compound are cubic, with a= 22.653 Å, Z= 32, space group Fd3c. The structure was solved from 249 counter intensities and refined by least-squares to R 4.46%. The [HgCl₅]^3– anion is a regular trigonal bipyramid, with axial bond lengths 2.518(4) and equatorial 2.640(4)Å. The highly significant difference between these values is compared with results for other MX₅ species and with theoretical predictions. Vibrational data are reported also and tentatively assigned.