Chemically controlled crystal growth of (CH3NH3)(2)AgInBr6

We report the successful crystal growth of a previously unknown mixed-metal organic compound (CH3NH3)(2)AgInBr6. This phase, which is not obtained by direct combination of reactants, is crystallized through the use of Pb2+ (from CH3NH3PbBr3) to modulate the soluble intermediates and force formation of (CH3NH3)(2)AgInBr6. Our results provide insights into mechanism and design-driven crystal growth and discovery of new halide materials that are chemically related to perovskites with photovoltaic and related applications.