CRYSTAL-STRUCTURES AND NONLINEAR-OPTICAL PROPERTIES OF CLUSTER COMPOUNDS [MAU2S4(ASPH3)(2)] (M=MO OR W)

The compounds [MAu2S4(AsPh3)(2)] (M = Mo 1 or W 2) were synthesized by reactions of [NEt4](2)[MS4] (M = Mo or W), HAuCl4 . 4H(2)O and AsPh3 in CH2Cl2 solution. X-Ray crystallographic structure determinations sh ow that the co-ordination of Mo(W) is slightly distorted from tetrahed ral and those of the Au are distorted from trigonal planar. High non-l inear susceptibilities of these gold-containing clusters were also obs erved for the first time. Z-Scan data measured with 532 nm nanosecond laser pulses showed that effective third-order non-linearities alpha(2 ) = 7.9 x 10(-5) and 13 x 10(-5) dm(3) cm W-1 mol(-1) and n(2) = -8.0 x 10(-10) and 19 x 10(-10) dm(3) cm(2) W-1 mol(-1),respectively for a 0.64 mmol dm(-3) solution of compound 1 and a 0.54 mmol dm(-3) solutio n of 2.