Electron collisions with methyl-substituted ethylenes: Cross section measurements and calculations for 2-methyl-2-butene and 2,3-dimethyl-2-butene.

We report electron-scattering cross sections determined for 2-methyl-2-butene [(H3C)HC = C(CH3)2] and 2,3-dimethyl-2-butene [(H3C)2C = C(CH3)2] molecules. Absolute grand-total cross sections (TCSs) were measured for incident electron energies in the 0.5-300 eV range, using a linear electron-transmission technique.