Knowledge Bank

The synthesis of nitrosylcyanide NC--NO has been described recently. The current report deals with a determination of the vibrational fundamentals of the compound. The molecule is planar but non-linear and has $C1v$ symmetry. There are five $A\prime$ fundamentals and one $A\prime$ fundamental, all of which are IR and Raman allowed. The normal coordinate analysis using the Wilson FG Matrix, method has resulted in the calculation of the $A\prime$ fundamental frequencies at $2376.4cm-1$ ($C\equiv $N stretch), $1052.7cm-1$ ($C-N$ stretch) $1466.5cm-1$ ($N=O$ stretch), and the A vibration at $54cm-1$ ($N\equiv C-N$ out-of-plane vibration). The calculations of the remaining $A\prime$ fundamentals ($N\equiv C-N$ and $C-N=O$ angle deformations) are currently being refined. The values of the diagonal force constants used in the calculations are as follows: [FIGURE] The calculated frequencies compare very well with the three frequencies that have been determined spectroscopically. These frequencies are $2180cm-1$ ($C\equiv N$ stretch) $819cm-1$ ($C-M$ stretch) and $1500cm-1$ ($N=0$ stretch).