Mobilities of Li(+)-attached butanol isomers in He gas.

Mobilities of Li+-attached butanol isomers, (n-BuOH)Li+, (s-BuOH)Li+, (i-BuOH)Li+, and (t-BuOH)Li+, in helium gas were measured over a range of reduced electric fields (E/N = 25–96 Td) at room temperature. Arrival time measurements accurately identified small differences in the measured mobilities of the isomer ions. At low E/N (⩽30 Td, corresponding to a mean collision energy ɛ¯≤0.05 eV), (n-BuOH)Li+ showed a mobility about 1.5% greater than that of the other ions, but at high E/N (⩾75 Td, ɛ¯≥0.1 eV) its mobility was about 1.1% less.