An Informal Overview of the Unitary Group Approach
Abstract
The Unitary Groups Approach (UGA) is an elegant and conceptually unified approach to quantum structure calculations. It has been widely used in molecular structure calculations, and holds the promise of a single computational approach to structure calculations in a variety of different fields. We explore the possibility of extending the UGA to computations in atomic and nuclear structure as a simpler alternative to traditional Racah algebrabased approaches. We provide a simple introduction to the basic UGA and consider some of the issues in using the UGA with spindependent, multibody Hamiltonians requiring multishell bases adapted to additional symmetries. While the UGA is perfectly capable of dealing with such problems, it is seen that the complexity rises dramatically, and the UGA is not at this time, a simpler alternative to Racah algebrabased approaches.
 Authors:
 Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)
 Louisiana State Univ., Baton Rouge, LA (United States). Dept. of Physics and Astronomy
 Publication Date:
 Research Org.:
 Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)
 Sponsoring Org.:
 USDOE
 OSTI Identifier:
 1258517
 Report Number(s):
 LLNLTR694837
TRN: US1601513
 DOE Contract Number:
 AC5207NA27344
 Resource Type:
 Technical Report
 Country of Publication:
 United States
 Language:
 English
 Subject:
 74 ATOMIC AND MOLECULAR PHYSICS; 73 NUCLEAR PHYSICS AND RADIATION PHYSICS; U GROUPS; ALGEBRA; HAMILTONIANS; CALCULATION METHODS; MOLECULAR STRUCTURE; NUCLEAR STRUCTURE; ELECTRONIC STRUCTURE; COMPARATIVE EVALUATIONS
Citation Formats
Sonnad, V., Escher, J., Kruse, M., and Baker, R. An Informal Overview of the Unitary Group Approach. United States: N. p., 2016.
Web. doi:10.2172/1258517.
Sonnad, V., Escher, J., Kruse, M., & Baker, R. An Informal Overview of the Unitary Group Approach. United States. doi:10.2172/1258517.
Sonnad, V., Escher, J., Kruse, M., and Baker, R. Mon .
"An Informal Overview of the Unitary Group Approach". United States.
doi:10.2172/1258517. https://www.osti.gov/servlets/purl/1258517.
@article{osti_1258517,
title = {An Informal Overview of the Unitary Group Approach},
author = {Sonnad, V. and Escher, J. and Kruse, M. and Baker, R.},
abstractNote = {The Unitary Groups Approach (UGA) is an elegant and conceptually unified approach to quantum structure calculations. It has been widely used in molecular structure calculations, and holds the promise of a single computational approach to structure calculations in a variety of different fields. We explore the possibility of extending the UGA to computations in atomic and nuclear structure as a simpler alternative to traditional Racah algebrabased approaches. We provide a simple introduction to the basic UGA and consider some of the issues in using the UGA with spindependent, multibody Hamiltonians requiring multishell bases adapted to additional symmetries. While the UGA is perfectly capable of dealing with such problems, it is seen that the complexity rises dramatically, and the UGA is not at this time, a simpler alternative to Racah algebrabased approaches.},
doi = {10.2172/1258517},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Mon Jun 13 00:00:00 EDT 2016},
month = {Mon Jun 13 00:00:00 EDT 2016}
}

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