Electronically stimulated sputtering of insulating molecular gas solids is a remarkably efficient process at excitation densities accessible by MeV light ions and keV electrons. This paper concentrates on the cases of CO and H 2O (D 2O). The approximately quadratic dependence of sputtering yield on the excitation density along individual particle tracks observed earlier for incident MeV ions has also been found for incident keV electrons in the case of CO. Coupled with time-of-flight energy spectra of ejected D 2O from solid D 2O, this behavior leads to a picture of rapid electronic relaxation with molecular repulsion involving pairs of molecular ions. We also report a dependence of CO sputtering yield on incident angle for MeV He ions which varies as (cos θ) −1.6, in qualitative support of the multiple ion picture. In addition to ejection of the principal molecular species of a solid film, electronic excitation of molecular solids even at very low temperatures leads to formation of new molecular species by bond disruption and fragment rearrangement. In the case of D 2O the dominant new molecules are D 2 and O 2 whose ejection from the film is strongly thermally activated.