Interstellar Grain Photochemistry

Studies on the effects of ultraviolet (UV) photons impinging on dust grains have revealed their importance for the interstellar chemistry evolution. While grain surface reactions generally produce simple molecular ice mantles, UV irradiation leads to the formation of more complex species, enhancing thus the interstellar gas phase. In fact, species as complex as sugars and amino acids have been obtained in laboratory experiments by irradiating ice analogs with UV photons. This demonstrates the key role of the interstellar grain photochemistry in the formation of the building blocks of life. This article aims to review the main advances carried out on interstellar grain photochemistry over the last decades, as well as the different approaches and techniques used.