A new anion,[Hg_2(SCN)_7]~(3-) :First synthesis,spectroscopic characterization and X-ray structure determination of [Co(NH_3)_6][Hg_2(SCN)_7]

摘要

The reaction of [Co(NH_3)_6]Cl_3 with a mixture of HgCl_2 and NH_4SCN in 1:2:8 molar ratio in hot aqueous medium leads to formation of a new complex salt,[Co(NH_3)_6][Hg_2(SCN)_7] (1) in 70% yield.This hexaamminecobalt(III) complex salt has been characterized by elemental analyses,solubility measurement and spectroscopic techniques (e.g.UV/Visible,IR and ~(13)C NMR).Single crystal X-ray structure determination of 1 revealed the presence of discrete [Co(NH_3)_6]~(3+) cation and a new anion,[Hg_2(SCN)_7]~(3-).This is the first report of a complex salt containing the new anion.The crystal lattice of the complex salt is stabilized by electrostatic forces of attraction and N-H...N (thiocyanate) hydrogen bonding interactions.