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Correlation energy extrapolation by intrinsic scaling. III. Compact wave functions
Laimutis Bytautas1, Klaus Ruedenberg
1Department of Chemistry and Ames Laboratory/USDOE, Iowa State University, Ames, IA 50011, USA.
The Journal of Chemical Physics
|January 7, 2005
Summary
This study shortens electronic wave function expansions using intrinsic scaling, maintaining chemical accuracy. Natural orbital participation is limited to reduce computational cost in electronic structure calculations.
Area of Science:
- Quantum Chemistry
- Computational Chemistry
Background:
- Full configurational expansions are computationally expensive.
- Approximations are needed to make electronic structure calculations feasible.
Purpose of the Study:
- To develop a method for shortening electronic wave function expansions.
- To maintain chemical accuracy while reducing computational cost.
Main Methods:
- Extrapolating correlation energy by intrinsic scaling.
- Truncating configurational expansions by limiting natural orbital participation.
Main Results:
- Successfully shortened electronic wave function expansions.
- Preserved chemical accuracy in truncated expansions.
Conclusions:
- Intrinsic scaling provides an effective way to reduce computational expense.
- Limited natural orbital participation is a viable strategy for accurate electronic structure calculations.
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