Presented here are the ionothermal preparation and structural variation of selenidostannates, whose structures can be tuned by varying the combination of ionic liquids and auxiliary amines as mixed solvent, as well as changing the reaction temperature and time. Remarkably, a silver-selenidostannate compound featuring lamellar structure was achieved by unusual insertion of linear two-coordinate Ag(+) ions between the {Sn(3)Se(7)}(n)(2n-) double chains.