Electrons, excitons and hydrogen bonding: electron-promoted desorption from molecular ice surfaces.

Desorption of benzene (C6 H6 ) from thick methanol (CH3 OH) and diethyl ether (CH3 CH2 OCH2 CH3 ) ices during irradiation with 250 eV electrons is reported and compared with our previous work on C6 H6 desorption from water (H2 O) ice systems. C6 H6 electron-promoted desorption (EPD) is seen to be sensitive to the chemical nature of the substrate reflecting both the importance of the excitations localised around the O-atom versus those involving the C-atom; and the role of hydrogen bonding interactions in transporting non-dissociative electronic excitation to the substrate/C6 H6 interfaces during the electron irradiation.