increased by about a factor of 2 going from the rod sides to corners, agreeing with prior simulations of AuNRs under transverse LSPR excitation showing the field enhancement differs by within an order of magnitude between these sites. Magnitudes of the evaluated hot electron generation rates-reported here as fluxes incident on the midplane AuNR cross section-are similar to prior simulation results. Previous work by Chen et al. estimated volumetric hot electron generation rates as high as 4 x 10 24 e -/(m 3 s) for individual AuNRs under illumination by a broadband light source. Movsesyan et al. calculated AuNR surface hot electron generation rates to be on the order of 10 23 -10 24 e -/(m 2 s) under longitudinal or transverse LSPR excitation. ). This discrepancy is explained by the range of physicochemical processes during the experiment, which provide alternative carrier relaxation pathways. Recombination of hot electrons with hot holes or electron scavengers will decrease the concentration of hot electrons available to react with silver and gold ions. Hot electrons are generated by Landau damping within ~100 femtoseconds of plasmon excitation and rapidly thermalize within the next few picoseconds through electron-phonon and electron-electron scattering processes. Decay and recombination processes render the lifetimes of hot carriers extremely brief (~fs-ns) compared to the timescale of chemical reactions (~ms-s). Furthermore, hot electrons have a broad energy distribution, so a fraction could have insufficient reducing power to reduce silver and gold ions. Altogether, the efficiency of plasmon energy conversion to indirect transfer processes-a primary mechanism to inject hot electrons from plasmonic metal nanostructures to adsorbates-has been estimated at < 1%. In view of these considerations, it is reasonable that a large fraction of hot electrons did not participate in the chemical reactions leading to metal deposition. The discrepancy between the simulated hot electron generation rate and metal deposition rate, i.e., one in every 10 7 -10 10 hot electrons produced a metal atom, provides an important experimental estimate of the fraction of hot electrons that can participate in the probe reaction.