Vibrational spectra of sulfito and hydrogensulfito complexes of iridium

For the diaquadichlorodisulfitoiridates(III) M ₃[IrCl ₂(SO ₃) ₂(OH ₂) ₂]·nH ₂O(M=Na, n = 7( 1); M = K, n = 2( 2)) some findings in vibrational spectra at ambient and low temperatures and estimated force constants f(IrO) and f(IrCl) are correlated with data from X-ray structure analyses. In the spectra of dichlorobis(hydrogendisulfito)iridates(III) trans-M ₅[IrCl ₂{(SO ₃H)(SO ₃)} ₂]·nH ₂O(M = Na, n = 10( 3); M = K, n = 5( 4)) the consequences of the short intramolecular hydrogen bonds for the valence vibrations of the sulfate ligands are discussed. From the vibrations of the O-H…O systems only the δ mode could be identified.