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Updated: Oct 21, 2025
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Probe Type II Band Alignment in One-Dimensional Van Der Waals Heterostructures Using First-Principles Calculations
Published on: October 12, 2019
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Improving MP2 bandgaps with low-scaling approximations to EOM-CCSD
Malte F Lange1, Timothy C Berkelbach1
1Department of Chemistry, Columbia University, New York, New York 10027, USA.
The Journal of Chemical Physics
|September 2, 2021
Summary
Partitioned equation-of-motion MP2 (P-EOM-MP2) offers improved semiconductor bandgap predictions compared to standard MP2. This method shows promise for accurately calculating electronic properties in materials science.
Area of Science:
- Computational materials science
- Quantum chemistry
- Solid-state physics
Background:
- Second-order Møller-Plesset perturbation theory (MP2) accurately predicts ground-state properties but underestimates semiconductor and insulator bandgaps.
- Accurate bandgap prediction is crucial for understanding and designing electronic materials.
Purpose of the Study:
- To evaluate the bandgap predictions of partitioned equation-of-motion MP2 (P-EOM-MP2).
- To compare P-EOM-MP2 performance against the G0W0 approximation for elemental and binary semiconductors and insulators.
Main Methods:
- P-EOM-MP2, a second-order approximation to EOM coupled-cluster theory with single and double excitations, was applied.
- Calculations were performed on a test set of elemental and binary semiconductors and insulators.
Main Results:
- P-EOM-MP2 overestimates bandgaps by an average of 0.3 eV.
- This contrasts with the G0W0 approximation (Perdew-Burke-Ernzerhof reference), which underestimates bandgaps by 0.6 eV on average.
- P-EOM-MP2 shows better performance for large bandgap materials, while G0W0 is superior for small bandgap materials.
Conclusions:
- P-EOM-MP2 provides a valuable alternative for bandgap calculations, offering improved accuracy over MP2.
- The performance differences between P-EOM-MP2 and G0W0 are linked to their respective treatments of screening and exchange interactions.
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