Stopping and straggling mean excitation energies, related properties, and their additivity, for the normal alkanes

Reliable values for the mean excitation energies for the stopping and straggling of fast charged particles in matter, I0 and I1 respectively, and the related dipole oscillator strength sums L0, S1, L1, and S/sub 1/2/, have been determined for the normal alkanes C/sub n/H/sub 2n + 2/, n = 1, 2, ..., 8, by using dipole oscillator strength distributions. The results are used to examine the validity of the additivity rules for the various dipole properties which prove very reliable for n > 1 if the elemental carbon and hydrogen properties used in the additivity relations are obtained from H2 and C2H6. Included is a discussion of how the validity of the additivity rules varies as a function of the dipole property