摘要:
                                In acid media Cu(I) and Ag(I) form complexes with planar dithiooxamides (LH(2)) of formula M(LH(2))(1)X(1). Complexes with dithiooxamide (DTO), N-methyldithiooxamide (MDTO) and N,N'-dimethyldithiooxamide (DMTO) have been prepared. Although all complexes studied have the same formula, different structures, depending on the halogen and the ligand used, are formed, as is shown by a thorough study of the vibrational spectra of these compounds. The M(DMDTO)(1)X(1) (X is Cl, Br) complexes and Cu(MDTO)(1)Cl-1 are found to form binuclear complexes with bridging halogens, wherein the ligand exhibits an S-cis structure. For the other complexes studied, the dithiooxamide has an S-trans conformation and polymeric structures are formed. In the case of Ag(DTO)(1)Cl-1, Ag(MDTO)(1)Cl-1 and Cu(DTO)(1)Cl-1 terminal metal-halogen bonds are present and trigonal coordination around the metal is proposed, while for Cu(DTO)(1)Br-1 and the Cu(LH(2))(1)I-1 complexes bridging halogens are present in the structure, giving a tetrahedral coordination. For Cu(MDTO)(1)Br-1 two different types of complexes could be obtained.