The Crystal Structure of Phenylmercury(II) Trifluoroacetate and the Refinement of the Crystal Structure of Phenylmercury (II) Acetate

The crystal structure o•f phenylmercury(I!) trifluoroace·tate (A) has been determined by the heavy-atom method using diffractometer X-ray diffraction data and refined by the least- squa.res procedure to the conventiona.l R index o.f 0.051. The structure of phenylrrnercury(II) aceta.te (B) has also been redetermined and refined also with diffractometer data in order to obtain better values for bond lengths and angles and to compare them w.ith those of CA). For (B) .the refdnement converged at an R index of 0.069. Both compounds, CA) and (B) , have essentially the same molecuLar structure: characteristic coordination of mercury is digonal witih ·almost co1\u27linear C-Hg-0 bonds. In both structures the angles at the Hg atoms are identical and amount to 176.6°. The Hg-C and Hg-0 bond lengths are 205.l and 212.1 pm in (A) , and 203.8 and 208.4 pm in (B) , respec,tively. The effective cooi\u27dination number of mercury in both structures is four: the mercury atoms, apart from being bonded to the phenyl-carbon and tri.fluoroacetato or acetato- oxygen atoms, are addition:a:lly sunounded in (A) by two trifluoroacetato- oxygen a.toms, in (B) by two acetato-oxygen atoms. The Hg .. . 0 distances vary frnm 281.9 to 295.2 pm