Structure of Bisaquamercury(II) Trifluoromethanesulfonate

The structurea nd bonding in bisaquamercury(I1) trifluoro~nethanesulfonate, [Hg(OH2)2(CF;S03)2ld, has been studied by means of single-crystal X-ray diffraction. The bisaquamercury(I1) trifluoro~nethanesulfonate shows an unusual bonding pattern where the mercury(l1) ion strongly binds two water molecules and four olygen atonis from four trifluoro~nethanesulfo~iatieo ns conpletea tetragonally co~npressed octahedral coordination geometrj, with the mean Hg-O bond distances 2.1 1 and 2.54 A. respectivel?. The tritluoro~nethanesulfonate ions form double bridges between the bisaquamercury(I1) entities giving rise to infinite >Hg(OH2)2<(CF;S01)2,Hg(OH2)2< chains. which are held together in sheets by relatively strong hqdrogen bonds with 0(-H) 0 distances in the range 2.690(9)- 2.736(9) A. The sheets are co~inected only vza van der Waals interactions between the -CF; groups protruding from the layers giving a fragile layer structure.