STRUCTURAL PECULIARITIES OF MIXED-LIGAND Zn(II) DIALKYLDITHIOCARBAMATE COMPLEXES WITH NITROGEN-CONTAINING HETEROCYCLES. L.A.Glinskaya, R.F.Klevtsova, S.M.Zemskova, S.V.Larionov, Institute of Inorganic Chemistry , Novosibirsk 90, Russia

An aimed synthesis and a structural study of a large group of chemical compounds with variable properties of ligands or metals make possible to establish a composition-structure-property correlation. We have synthesized some volatile mixed-ligand complexes (MLC) of zinc(II) dialkyldithiocarbamates with (i)alkyl substituents of a different length and with different steric structures; (ii) various N heterocycles i.e., Phen(L1), 2,2'-Bipy(L2), 4,4'-Bipy(L3). Single crystals were prepared and studied by X-ray structure analysis. Structural features of five MLC were discussed.

N      Complexes            Zn-S      Zn-N      CN    
1    Zn(Et2Dtc)2 L1  P1(-)  2.44-2.6  2.18;     6     
                            4         2.25            
2    Zn(Et2Dtc)2 L2  Pnaa   2.49-2.5  2.18;     6     
                            7         2.18            
3    Zn(Me2Dtc)2 L1  C2/c   2.45-2.5  2.18;2.2  6     
                            7         1               
4    Zn2(Et2Dtc)4    Pnca   2.33-2.6  2.10      5     
     L3                     3                         
5    Zn2(i-Bu2Dtc)4  P1(-)  2.33-2.6  2.07      5     
     L3                     4                         

The crystal structures consist of monomeric (1-3) or binuclear (4,5) molecules linked through van der Waals contacts. Coordination polyhedra of the central Zn atom are a distorted tetragonal pyramid and a trigonal bipyramid for CN =5, and a distorted octahedron for CN=6. We have considered a molecule packing mode and revealed a correlation between Zn-S and Zn-N distances and a polyhedron shape. The thermal properties of MLC in vacuum and in air were studied. This research allowed us to introduce some MLC as molecular precursors for preparing ZnS films by the CVD method.