First optical non-linearity study on Group 6 Group 10 sulfide mixed-metal complexes, synthesis and crystal structure of [NEt4][PdWS4(S2CNC4H8)] and [NEt4](2)[PdW2S8]

Two Group 6-Group 10 sulfido mixed-metal complexes, [NEt4][PdWs(4)(S2CNC4H8)] 1 and [NEt4](2)[PdW2S8] 2, have been synthesized via reactions of [Pd(S2CNC4H8)(2)] with [NH4](2)[WS4] and NEt4Cl in different molar ratios in dichloromethane. X-Ray crystallographic structure determinations revealed that palladiumin 1 is co-ordinated by a pyrrolidinecarbodithioate and a tetrathiotungstate, while in 2 it is co-ordinated by two tetrathiotungstates symmetrically. Both dithiocarbamate and tetrathiotungstate act as bidentate ligands through two sulfur atoms chelating palladium. The Pd-W distances are 2.8669(7) and 2.9008(5) Angstrom in 1 and 2, respectively. Non-linear optical properties of the compounds were studied with a 7 ns pulsed laser at 532 nm. Compound 1 exhibits mainly optical self-defocusing (n(2) = -6.8 x 10(-18) m(2) W-1 as measured with a 1.0 x 10(-3) mol dm(-3) acetonitrile solution) with negligible non-linear absorption. Compound 2 exhibits both optical self-defocusing (n(2) = -7.5 x 10(-18) m(2) W-1, as measured with a 1.6 x 10(-3) mol dm(-3) acetonitrile solution) and optical non-linear absorption(alpha(2) = 3.5 x 10(-11) m W-1).