Structures of mercury(II) halide adducts with transition-metal Lewis bases. Part II. Crystal structure of the 1 : 3 complex between dicarbonyl-π-cyclopentadienylcobalt and mercury(II) chloride

Abstract

Crystals of (π-C₅H₅)(CO)₂Co,3HgCl₂ are triclinic, a= 10·080, b= 12·572, c= 7·144 Å, α= 87·82, β= 95·67, γ= 108·7°, and Z= 2 in space group P. The structure was solved from photographic data by Patterson and Fourier methods and refined by least squares to R 0·095 for 1354 observed reflections. Unlike (π-C₅H₅)(CO)₂Co, HgCl₂ which is an adduct, this complex is best formulated as a salt, [(π-C₅H₅)Co(CO)₂(HgCl)]⁺Cl^–, with two additional molecules of mercury(II) chloride. The cation contains an Hg–Co bond (2·504 ± 0·009 Å) which is significantly shorter than that found in the 1 : 1 adduct (2·578 ± 0·004 Å).