Knowledge Bank

The infrared spectrum of cyanamide, HHNCN, has been recorded from $500cm-1$ to $4000cm-1$ using a Digilab FTS 208 fourier transform spectrometer operating with a resolution of $0.09cm-1$. Samples of cyanamide were deposited in the infrared cell which was two meters in length. The entire cell was held at a temperature of 373 K, thus providing enough vapour pressure of cyanamide for the infrared absorption spectra. All fundamental bands of cyanamide including the inversion hot bands except the NCN bending modes have been detected. The rotational structure of the unperturbed part of the $0\mathrm{<mrow\; data-mjx-texclass="ORD">+</mrow>}-1\mathrm{<mrow\; data-mjx-texclass="ORD">-</mrow>}$ C-type band, which shows a-type Coriolis interaction for $Ka$ greater than 2, has been assigned and analysed. The band center and the rotational constants of the 1$\mathrm{<mrow\; data-mjx-texclass="ORD">-</mrow>}$ state were obtained. Furthermore, three band systems of carbodiimide, HNCNH, were observed under the same experimental conditions. All three bands have previously been observed in the infrared spectra of argon matrix-isolated cyanamide and carbodiimide (1), however, no gas phase spectra were reported. The present results confirm the thermal isomerization of cyanamide. The current state of the analysis of these bands will be reported.