Elastic scattering of slow electrons by n-propanol and n-butanol

We report measured and calculated cross sections for elastic scattering of low-energy electrons by the alcohols n-propanol and n-butanol in the gas phase. The measurements were carried out using the relative-flow method with an aperture source rather than a conventional tube or capillary-array source, eliminating the need to know molecular diameters. The calculations employed two different implementations of the Schwinger multichannel variational method and included polarization effects. The differential cross sections are dominated by strong forward scattering due to the molecules' large electric dipole moments, but near 10 eV, they display structure at intermediate angles that is probably associated with shape resonances, notably a pronounced f-wave scattering pattern. Overall agreement between the measured and calculated results is fair. We compare the cross sections of these larger alcohols to those of methanol and ethanol, as well as to those of alkanes.