The fascinating noncentrosymmetric copper(II) phosphates synthesized via CsCl salt-inclusion

Two new noncentrosymmetric (NCS) solids were isolated via high-temperature, salt-inclusion reactions, Cs2Cu7(P2O7)(4).6CsCl (1, CU-9) and Cs2Cu5(P2O7)(3).CsCl (2, CU-11). These copper(II) phosphates exhibit novel open-framework structures conceptually templated by extended Cs-Cl salt. The latter resides cooperatively in the channels upon the formation of the NCS Cu-P-O frameworks, leading to the formation of fascinating salt lattices centered by the NaCl-type core. These new discoveries are significant for they may give rise to a new route for the templated synthesis of NCS solids. We are to show here the structural correlation of the newly discovered hybrid solids, and the role of the chlorine atoms in the intergrowth of covalent/ionic sublattices.