Accession Number : ADA266970


Title :   Theoretical Prediction of the UV Adsorption and Fluorescence Spectra of Tyrosine and Phenylalanine


Descriptive Note : Final rept. May-Aug 92,


Corporate Author : BATTELLE MEMORIAL INST COLUMBUS OH


Personal Author(s) : Hameka, Hendrik F ; Jensen, James O


Full Text : https://apps.dtic.mil/dtic/tr/fulltext/u2/a266970.pdf


Report Date : May 1993


Pagination or Media Count : 25


Abstract : This report presents a theoretical study of the ground state and of the first excited state of phenylalanine and tyrosine to interpret the excitation absorption and the fluorescence emission spectra of the two molecules. The computations are performed with the Gaussian 90 Program Package using 3-21G basis sets. The ground state is computed with the HF option and the excited state with the Configuration Interaction, Single (CIS) Excitations option only. This report optimized the molecular geometries of both the ground and excited states and computed the excitation energies at both geometries. In conclusion, the excited state is due to a superposition of excitations from bonding orbitals in the alanine chain to a pi orbital in the benzene ring and to an orbital in the C-C bond attached to the ring.


Descriptors :   *FLUORESCENCE , *PREDICTIONS , *GROUND STATE , *ABSORPTION , *EXCITATION , *TYROSINE , *MOLECULAR ORBITALS , *PHENYLALANINE , *ULTRAVIOLET SPECTRA , BENZENE , INTERACTIONS , CARBON , SPECTRA , CHAINS , ALANINES , HYDROXYL RADICALS , AMINO ACIDS , RINGS , BONDING , CONFIGURATIONS , CHEMICAL BONDS , EMISSION SPECTRA , MOLECULES , QUANTUM CHEMISTRY , COMPUTATIONS


Subject Categories : Biochemistry
      Physical Chemistry
      Atomic and Molecular Physics and Spectroscopy
      Quantum Theory and Relativity


Distribution Statement : APPROVED FOR PUBLIC RELEASE