Solvothermal syntheses and structures of A3AgSn3Se8 (A = Rb, K)

Two new compounds A3AgSn3Se8(A = K, Rb) were synthesized solvothermally and characterized by X-ray single crystal diffraction. These compound are composed of building block [Sn3Se8]4− formed by three edge-sharing SnSe4 tetrahedra, and these building blocks are further connected by tetrahedral coordinated Ag+ to form infinite chains, alkali cations are located between the chains. Their optical properties were also studied.