[NH4]2[MoS4] reacts with CuBr and [Bu4N]Br in the solid state to afford an intermediate product with proposed constitution [Bu4N]4[MoS4Cu6Br8] (1). Treatment of cluster (1) with an equal equivalent of dppf in CH3CN–DMF solution resulted in the formation of a pentanuclear cluster [MoS4(Cudppf)2]·2DMF·CH3CN (2). Cluster (2) crystallizes in the monoclinic space group P21/n with four formula units in a cell of dimensions a
= 13.1267(8), b
= 38.040(2), c
= 15.2661(9) Å, and β
= 97.6030(10)°. Refinement by full-matrix least-squares techniques gave
final residuals R
= 0.0567 and wR
= 0.1679. The structure of (2) can be described as two (Cudppf)+ units linked through MoS42− to form a pentanuclear folding-ruler array. Reaction of (1) with excess Ph2PPy in CH3CN solution resulted in the formation of a trinuclear cluster [MoS4Cu2(Ph2PPy)4] (3). Cluster (3) crystallizes in the tetragonal space group I41/a with cell constants a
= 17.427(6), b
= 17.427(6), c
= 21.344(5) Å, and Z
= 4. Final residuals R
= 0.0337 and wR
= 0.0616. The structure of (3) is built up from
two Cu(Ph2PPy)2+ units bridged by a MoS42− ligand to form a trinuclear symmetrical linear molecule. Clusters (2) and (3) exhibit strong optical absorption (effective α2
= 1.6 × 10−9 m W−1 (2) and 1.2 × 10−9 m W−1 (3)) and optical self-defocusing effects (n2
=
−1.35 × 10−17 m2 W−1 (2) and −6.84 × 10−17 m2 W−1 (3)), their limiting thresholds were determined to be 0.35 J cm−2 (2)
and 0.65 J cm−2 (3), which are about four and two times, respectively, better than that of C60.
You have access to this article
Please wait while we load your content...
Something went wrong. Try again?