Synthesis, vibrational spectra, and crystal structures of the nitrato argentates (Ph4P)[Ag(NO3)2(CH3CN)].CH3CN and (Ph4P)[Ag2(NO3)3]

Tetraphenylphosphonium bromide reacts in acetonitril suspension with excess silver nitrate to give (Ph4P)[Ag(NO3)(2)(CH3CN)]center dot CH3CN (1), whereas (Ph4P)[Ag-2-(NO3)(3)] (2) is obtained in a long-time reaction from (Ph4P)Br and excess AgNO3 in dichloromethane suspension. Both complexes were characterized by vibrational spectroscopy (IR, Raman) and by single crystal structure determinations. 1: Space group P2(1)/c, Z = 4, lattice dimensions at 193 K: a = 1781.5(3) b = 724.8(1), c = 2224.2(3) pm, beta = 96.83(1)degrees, R-1 = 0.0348.1 contains isolated Complex units [Ag(NO3)(2)(CH3CN)](-), in which the silver atom is coordinated by the chelating nitrate groups and by the nitrogen atom of the solvated CH3CN molecule with a short Ag-N distance of 220.7(4) pm. 1753.4(4), b = 701.7(1), c = 2105.5(4) pm, R-1 = 0.072. In the polyrneric anions [Ag-2(NO3)(3)](-) each silver atom is coordinated in a chelating manner by one nitrate group and by two oxygen atoms of two bridging nitrate ions. In addition, each silver atom forms a weak pi-bouding contact with a phenyl group of the(Ph4P)(+) ions with shortest (AgC)-C-... separations of 266 and 299 pm, respectively, indicating a (4+1) coordination of silver atoms.