Infrared and Raman spectra of potassium pentacyanonitrosylmanganate(I) dihydrate: K3[Mn(CN)5NO]· 2H2O

The infrared spectra of polycrystalline K₃Mn(CN)₅NO]·2H₂O at different degrees of deuteration were recorded between 4000 and 200 cm^–1, both at room and low temperature. The room-temperature Raman spectrum of the isotopically normal powder was also obtained. The observed bands were assigned to the internal vibrational modes of the Mn(CN)₅NO]^–3 ion and to the internal and librational modes of water of hydration. In accordance with X-ray diffraction studies, the spectra showed the existence of two crystallographically distinct types of water molecules located in different sets of sites ofC ₁ symmetry.A communication on this subject was presented at the XVI Latin American Chemistry Congress, Rio de Janeiro, Brazil, October 14–20, 1984.