Cyanophosphaethyne


Cyanophosphaethyne is an unstable molecular compound with structural formula N≡C–C≡P. It can be considered as cyanogen with one nitrogen atom replaced by phosphorus. It has been made as a dilute gas. Cyanophosphaethyne has been tentatively detected in the interstellar medium. Other structural isomers, such as C≡N–C≡P, C≡C-N≡P, and N≡C–P=C, have not been observed. The molecule has linear molecular geometry.

Production

Cyanophosphaethyne can be produced by heating cyanogen azide and phosphaethyne gases to 700 °C:
Another method is to heat anhydrous methyl cyanide with anhydrous phosphorus trichloride:

Properties

The dipole moment is 3.5 Debye. Having a large dipole makes the molecule easier to detect by certain types of spectroscopy than many other phosphorus containing molecules. The bond lengths are C≡N = 1.159 Å, C–C = 1.378 Å, and C≡P = 1.544 Å.