Abstract: | By the application of cation substitution, a new mixed‐alkali metal diphosphate, K2Li2P2O7, was successfully synthesized through high temperature solution method for the first time. The single‐crystal X‐ray structural analysis shows that it crystallizes in the monoclinic space group C2/c (no. 15), with lattice constants a = 9.814(3) Å, b = 5.5163(15) Å, c = 13.538(4) Å, Z = 4, and β = 110.47(2)°. Its open cage‐like ∞3[Li2(P2O7)]2– framework is built up from alternating arrangement of Li2O6 and P2O7 dimers that form eight and twelve‐membered‐ring channels along the [010] direction, and the K atoms are entrapped in the larger twelve‐membered‐ring channels. Detailed structure comparisons in the N4P2O7 (N = mixed alkali metals) family are discussed. In addition, the structural validity was verified through the IR spectrum. Thermal analyses and UV/Vis/NIR diffuse reflectance spectrum are also performed on the reported compound. |