Résumé
The three-membered ring molecule, cyclopropenylidene (c-C3H2), discovered in space in 1985,1 has gained attention very rapidly because of its ubiquity in space. It is not a common molecule on Earth and it is not used in the laboratory for any synthesis. However, it is a stable interstellar species surviving even in UV exposed regions. The formation is due to the dissociative recombination (DR) of c-C3 H3+: $$c - {C_3}H_3^ + + {e^ - } \to c - {C_3}H_2^ + + H$$