Synthesis, characterizaiton and optical non-linearity of two heterobimetallic copper clusters containing tetraselenometalates

摘要

Cluster [(MoCu3Se3Br)(PPh3)3Se].3THF.H20 (1.3THF.H20) was prepared from reaction of [Et.sNlAMOSCVs, Cu(PPh5)2NO-~ si Et4N-Br in CH2CI2 solution: also, 1 can be also obtained from the reaction of [MoSe4Cu4Py6Br2I and excess PPh3 in a DMF— 12C12 mixture solvent. The ‘5Mo NMR technique was used to monitor the above two reaction processes. X-ray crystal-·graphic structure determination shows that it contains a strongly distorted cubane-like lMoCu;SesBr) core. The coordination the central Mo atom and each Cu atom are distorted from tetrahedral. Cluster [{ WCu5Se~C1 I (PPh3)3Se] (2) was synthesized the reaction of [Et4NIs[WSeI4 and Cu(PPh3)sCl in the solid state for nonlinear optical (NLO) studies, Its structure was eported by Ibers (Inorg. Chem. 31(1992) 4365). The NLO properties of clusters 1 and 2 were studied. Both NLO absorptionncl refraction were obtained, and their effective third-order non-linearities were detected with a2 = 3.4 X 10—10 and 5.9 X—10 m/Wandn2 = —1.5 x 10 17 and —1.3 x 10—17 m2fW, respectively, forthe same concentration CH,CI, solution ofland Influence of skeletal atoms to nonlinear absorption is also discussed in the paper.