A new nonlinear optical sulfate of layered structure: Cs2Zn2(SO4)3

Acentric structure is the indispensable condition for a compund to exhibit nonlinear optical (NLO) response. However, it’s difficult for inorganic sulfates to crystallize in acentric structures. In this communication, a new acentric sulfate, Cs2Zn2(SO4)3, has been synthesized by spontaneous crystallization method. The crystal structure of Cs2Zn2(SO4)3 is layered and is composed of Zn2(SO4)3 layers and Cs+ cations, which is different from A2B2(SO4)3 (A = K, Rb, B = Mg, Ca, Cd, Zn) type that owns three-dimensional framework. Powder NLO response suggest that Cs2Zn2(SO4)3 exhibits a moderate second-order NLO response of about 0.15 × KH2PO4. Theoretical calculations were performed and elucidated that the origination of NLO response is from SO4 groups and ZnOn (n = 4, 5) polyhedra. This work will enrich the diversity of sulfate structure and provide new desgin strategy on the synthesis of novel NLO sulfates.