Mapping out the conduction band under CTTS transitions: the photodetachment quantum yield of sodide (Na−) in tetrahydrofuran

Upon photoexcitation of the charge-transfer-to-solvent absorption band of Na− in tetrahydrofuran (THF), electrons detach into immediate contact pairs, solvent-separated contact pairs, or as free electrons. In this Letter, we analyze the recombination dynamics of Na− at multiple excitation wavelengths to determine the action spectrum for production of each type of electron. The action spectra match well with the four Gaussian sub-bands (corresponding to three p-like CTTS states and the continuum) needed to describe the polarized bleach recovery. We also find that the Na− free-electron action spectrum is linearly related to the Rb−/THF photocurrent action spectrum measured by Levanon and co-workers.