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Spectral density calculation by using the Chebyshev expansion
Tsutomu Ikegami1, Suehiro Iwata
1Department of Chemistry, University of Puerto Rico, San Juan 00931-3346, USA. ikegami@adam.uprr.pr
Journal of Computational Chemistry
|April 2, 2002
Summary
This study presents a new method for calculating spectral density using Chebyshev expansion and a spectral transformation function. The method accurately computes the predissociation spectrum of CO+ for improved low-energy resolution.
Area of Science:
- Quantum mechanics
- Computational chemistry
- Spectroscopy
Background:
- Calculating spectral densities is crucial for understanding molecular systems.
- Existing methods may lack resolution in specific energy regions.
Purpose of the Study:
- To develop a novel method for computing spectral density of state vectors.
- To enhance resolution in low-energy spectral regions.
Main Methods:
- Utilizing the Chebyshev expansion method to evaluate the spectral density operator.
- Introducing a spectral transformation function for improved resolution.
- Calculating the predissociation spectrum of CO+ as a demonstration.
Main Results:
- The proposed method successfully calculates spectral density.
- The spectral transformation function enhances low-energy spectral resolution.
- Accurate predissociation spectrum of CO+ was obtained.
Conclusions:
- The presented method offers an effective approach for spectral density calculations.
- The technique provides improved resolution in low-energy spectral analysis.
- This method is applicable to various quantum mechanical systems.
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