Accession Number : ADA466101


Title :   A Multireference Density Functional Approach to the Calculation of the Excited States of Uranium Ions


Descriptive Note : Doctoral thesis


Corporate Author : AIR FORCE INST OF TECH WRIGHT-PATTERSON AFB OH GRADUATE SCHOOL OF ENGINEERING AND MANAGEMENT


Personal Author(s) : Beck, Eric V


Full Text : http://www.dtic.mil/dtic/tr/fulltext/u2/a466101.pdf


Report Date : Mar 2007


Pagination or Media Count : 191


Abstract : An accurate and efficient hybrid Density Functional Theory (DFT)/Multireference Configuration Interaction (MRCI) model for computing electronic excitation energies in heavy element atoms and molecules was developed. This model incorporated relativistic effects essential for accurate qualitative and quantitative spectroscopic predictions on heavy elements, while simultaneously removing spin-multiplicity limitations inherent in the original model on which it is based. This model was used to successfully compute ground and low-lying electronic states for atoms in the first two rows of the period table, which were used for calibration. Once calibrated, calculations on carbon monoxide, bromine fluoride, the bromine atom, uranium +4 and +5 ions and the uranyl (UO2 2+) ion showed the model achieved reductions in relative error with respect to Time Dependent Density Functional Theory (TDDFT) of 11-42%, with a corresponding reduction in computational effort in terms of MRCI expansion sizes of a factor of 25-64.


Descriptors :   *IONS , *EXCITATION , *DENSITY FUNCTIONAL THEORY , *URANIUM , TIME DEPENDENCE , THESES , CONFIGURATIONS , COMPUTATIONAL CHEMISTRY , ELECTRON SPECTROSCOPY , CALIBRATION , ELECTRONIC STATES , QUANTUM CHEMISTRY , INTERACTIONS


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


Distribution Statement : APPROVED FOR PUBLIC RELEASE