FTIR and Raman spectra and structure of Cu(NO3)+ in aqueous solution and acetone

FTIR and Raman spectra of copper(II) nitrate hydrate dissolved in water, acetone and their fully deuterated counterparts indicate that the copper nitrate complex, CuNO+3, is formed at high solute concentration. The spectra show new bands that can be attributed to symmetry lowering of the complexed nitrate ion. Four possible structures are discussed for the complex, with Raman depolarization ratios favoring a complex with C2υ symmetry. A new Raman band at 335 cm−1 is assigned to the symmetric copper—oxygen stretch in a bidentate complex.