Heterobimetallic Cluster‐Based Coordination Polymers: Assembly, Structures and Third‐Order Nonlinear Optical Properties

Reactions of (NH 4 ) 2 WS 4 with CuCN, CuCN/1,2‐bis(4‐pyridyl)propane (bppa) or [Cu(MeCN) 4 ]PF 6 /bppa under different reaction conditions afforded a set of two‐ or three‐dimensional W/Cu/S cluster‐based coordination polymers including {[Et 4 N] 2 [WS 4 Cu 4 ( μ ‐CN) 2 ( μ ‐I) 2 ]} n ( 1 ), [WS 4 Cu 4 ( μ ‐CN) 2 (bppa) 2 ] n ( 2 ) and {[WS 4 Cu 4 (bppa) 4 ](PF 6 ) 2 } n ( 3 ), respectively. Compound 2 can be readily formed from reaction of 1 with bppa under solvothermal conditions. Compounds 1 and 2 feature two‐dimensional networks with a “sql” topology, while 3 possesses a two‐fold interpenetrated three‐dimensional net with a rare “reo ” topology. Compounds 1 – 3 in DMF exhibited different third‐order nonlinear optical responses, and they all showed a reverse saturable absorption while 2 held a strong self‐focusing effect.