Measurements of the optical absorption spectra of the sublimed films of adenine, guanine, cytosine, thymine, and uracil were extended down to 120 mp at room temperature. Several remarkable absorption peaks were found to exist below 190 mp in addition to the already known ones near 260 mp and 200 mp.
2511. Vacuum ultraviolet photoemission studies of nucleic acid bases
- Publisher
- Elsevier Science
- Year
- 1977
- Tongue
- English
- Weight
- 18 KB
- Volume
- 27
- Category
- Article
- ISSN
- 0042-207X
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β¦ Synopsis
Classified abstracts 2511 37. INORGANIC CHEMISTRY, ANALYTICAL CHEMISTRY, DISTILLATION 37 2511. Vacuum ultraviolet photoemission studies of nucleic acid bases. (USA)
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.
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