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Within a tight-binding approximation, we numerically determine the time evolution of graphene electronic states in the presence of classically vibrating nuclei. There is no reliance on the Born–Oppenheimer approximation within the p-orbital tight-binding basis, although our approximation is “atomically adiabatic”: the basis p-orbitals are taken to follow nuclear positions. Our calculations show that the strict adiabatic Born–Oppenheimer approximation fails badly. We find that a diabatic (lazy electrons responding weakly to nuclear distortions) Born–Oppenheimer model provides a much more accurate picture and suggests a generalized many-body Bloch orbital-nuclear basis set for describing electron–phonon interactions in graphene.
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This content will become publicly available on August 20, 2026
Understanding the bonding at the surface-adsorbate interface: Modulating the N-heterocyclic carbene-single atom alloy interface
We apply non-local density functional theory calculations to determine the impact of backbones and functionalization of different N-heterocyclic carbenes (NHCs) adsorbed to different single atom alloys (SAAs). A frontier molecular orbital approach is applied to these systems to understand the chemistry occurring. The Local Orbital Basis Suite Towards Electronic-Structure Reconstruction (LOBSTER) program was utilized to project an atomic orbital (AO) basis from our PAW simulations to allow for a MO-oriented bonding analysis MOs of the adsorbate molecules were extracted from our planewave VASP calculations utilizing the linear combination of fragment orbitals (LCFO) method implemented in LOBSTER.
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- Award ID(s):
- 2142874
- PAR ID:
- 10652034
- Publisher / Repository:
- American Chemical Society
- Date Published:
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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