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The spectral quantum yields of adenine, thymine, cytosine, and uracil films were measured at photon energies of 7 to 23 eV. In addition, photoelectron-energy-distribution measurements were made at 21.2 eV. The photoelectron spectra exhibit features which can be associated with density-of-states structures below the vacuum level. The difference between the observed photoemission threshold of a solid film and the calculated energy of the highest occupied orbital for the isolated molecule is found to be 1.5–2.0 eV.

Photoemission measurements on evaporated films of BaF2 and BaC12 were made at photon energies of 8-27 eV. Spectral quantum yields and energy distributions of photoemitted electrons were measured. The photoelectron spectra show high-density-of-states structures at 2.5+0.2, 5.2+0.2, and 7.5+0.2 eV above the vacuum level for BaF, and 3.5+0.2 eV above the vacuum level for BaC1,. The spectra also provide information on the valence-band widths, band thresholds, and the spin-orbit splitting of the Ba++ 5p core band of BaC12. The energy differences between the regions of initial and final high densities of states are compared with the transition energies of certain structures found in the optical and energy-loss spectra of BaF,.