Abstract: The effects of structure and stereochemistry on the gas-phase ionization of P- substituted ethanols (XCHzCHzOH), propanols (CH3CH (OH) CH2X and CH3CHXCH20H), and cyclopentanols have been studied by ion cyclotron resonance techniques. Ionization to form XCzH4+, XC3H6+, or XCsHs+, where X= F, C1, Br, OR, SR, SH, and NH,, occurs as the result of protonation of the alcohol and subsequent dissociation with HzO as the leaving ...