Notes. Band positions are colour-coded according to their behaviour during post-irradiative warming of the ice: those written in blue and red, respectively, undergo blueshifting and redshifting upon warming, while those written in black do not vary in their wavelength position within 1 nm during warming. Species that have closely overlapping features and are not separable in our spectra prior to their desorption during warming are grouped into the same columns. Note that these are the observed band positions in our spectra, as opposed to absolute band positions of the specific molecules’ features. Due to overlapping absorption features, the band positions ascribed to the (cyano)polyyne species in this table may be shifted relative to what their positions would be in ices comprised entirely of the respective (cyano)polyyne species. ^†Band identification is tentative. ^*We observed splitting of this peak in the neat C₂H₄ experiment after electron irradiation. The splitting vanished after warming. (See Figure 2e).