Synthesis, Characterization and Theoretical Investigation on the Optical Nonlinearity of WS4Co(dppe)(DMF) Heterometallic Cluster Compound

A novel hetero-metallic binuclear cluster WS4Co(dppe)(DMF) has been synthesized and characterized. The crystal has a structure of monoclinic space group P21. Ab initio CPHF calculations are performed on the static first hyperpolarizabilities of the molecular building blocks of the cluster. The microscopic structural origin of nonlinear optical properties are discussed in-depth. The charge-transfer between tungsten ion and cobalt ion in a molecular building block critically contributes to the optical nonlinearity, while the joint effect of the ligands makes sufficient enhancements. The study is helpful to search for novel IR nonlinear optical materials among the transition metal cluster compounds.