Upper panel: Absorption profile of the combination mode of methyl cyanide, around 1448.3 cm⁻¹ (6.905 µm), in pure and mixed ices. The ice spectra at different temperatures are indicated by different colors and labels. Bottom left: Peak position and FWHM of the combination mode of CH₃CN in different ice mixtures at selected temperatures. Bottom right: relative band strengths of the combination band in different ice mixtures at 15 K.