Top row: TPD of ¹³CO (m/z = 29) used to calculate k_CO for UV experiments (left) and electron experiments (right). Bottom two rows: the temperature-programmed desorption (TPD) of ¹³CO (m/z = 29; middle) and of ¹⁵N₂ (m/z = 30; bottom) without any irradiation. From left to right: primary, binary, ternary. Some of the TPD curves have been scaled for readability, which is listed on the individual panel.