Reaction of H atoms with solid C2H4 and C2H6 at 13 K

The reaction of H with solid thin films of C2H4 and C2H6 deposited on the silicon substrate at 13 K was studied using the thermal desorption method and Fourier transform-infrared (FT-IR) spectroscopy. In the reaction of H with C2H4, the formation of C2H6 as a major product and C4H10 as a minor one was observed. The high yield of C2H6 formed from the low-temperature tunneling reaction suggests the occurrence of efficient conversion of C2H4 into C2H6 on the cold dust grains. In the reaction of K with C2H6, no reaction products were detected, suggesting that the recombination reaction H + C2H5 --> C2H6 prevails in the solid phase.