Continuous wave (CW) and pulsed acetonitrile and acrylonitrile plasmas have been used to deposit thin nitrogen-containing films. Changes in film composition with applied CW power and pulse duty cycle have been monitored using Fourier transform infrared spectroscopy (FTIR) and deposition rates have been measured for both systems. A detailed description of FTIR peak assignments is presented and shows that the composition of films deposited from acetonitrile are insensitive to CW input power and duty cycle. In contrast, acrylonitrile films exhibit a strong compositional dependence on CW input power and duty cycle with the growth of highly conjugated imine and nitrile species. These monomer dependent compositional changes are discussed in terms of their structure, pulse off time durations, and equivalent pulsed and CW applied rf powers. Optical emission spectroscopy (OES) and deposition rate data afford further insight into film formation processes with the two monomers.