Structural studies of lanthanide ion complexes of pure gold, pure silver and mixed metal (gold silver) dicyanides

Crystal structures of four lanthanide complexes of La [Au(CN)(2)](3) . 3H(2)O, La [Ag(CN)(2)](3) . 3H(2)O, La [Ag0.83Au0.17(CN)(2)](3) . 3H(2)O, and La [Ag0.39Au0.61(CN)(2)](3) . 3H(2)O are reported. Studies reveal that all the structures reported are isostructural. All systems were found to be in the hexagonal crystal system, space group P6(3)/mcm. The metal metal distance for the pure gold system is 3.332 ( 1) Angstrom versus 3.359( 1) Angstrom for the pure silver system. The mixed-metal systems have shown no distinct differences in the location of the metal atoms, with the La [Ag0.83Au0.17(CN)(2)](3) . 3H(2)O complex having a metal metal Ag-Au separation of 3.346( 1) Angstrom, and 3.344( 1) Angstrom for the La [Ag0.39Au0.61(CN)(2)](3) . 3H(2)O complex. The crystal structures of the pure and mixed La complexes have been solved to provide evidence of Ag-Au heterometallic interactions and as a basis for understanding the interesting optical properties of the systems.