Solutions of 1-2 mol% of pentane, pentane-3-d2, pentane-2, 4-d4, and pentane-1, 5-d6 in CFCl,, CF3CC13, and CF2ClCFC12 have been X irradiated at 77 K. ESR spectra of the molecular ions were recorded at temperatures between 77 K and either the glass transition temperature for CF3CC13 (140 K) and CF, ClCFCl,(about 110 K) or the melting point for CFC13 (162 K). It was found that the pentane molecular ions in these matrices have not ...