TPD signatures of hydrogen loss from ethanol in experiment N. On the left, relevant mass channels for acetaldehyde and vinyl alcohol are shown and compared to reference mass spectra obtained from Chuang et al. (2020). On the right, RAIR spectra are shown at several temperatures, indicating the changes in peak intensity. Note that the peak positions 1715 and 1678 / 1636 cm⁻¹ correspond to CH₃CHO and CH₂CHOH respectively.