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Size-Consistent Adiabatic Connection Functionals via Orbital-Based Matrix Interpolation

delete2026-01-01
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PRE
AI
K
Kyle Bystrom
T
Timothy C. Berkelbach *
DOI:10.1021/acs.jctc.5c01850delete
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Abstract

Abstract

En 中文
We introduce a size-consistent and orbital-invariant formalism for constructing correlation functionals based on the adiabatic connection for density functional theory (DFT). By constructing correlation energy matrices for the weak and strong correlation limits in the space of occupied orbitals, our method, which we call orbital-based size-consistent matrix interpolation (OSMI), avoids previous difficulties in the construction of size-consistent adiabatic connection functionals. We design a simple, nonempirical adiabatic connection and a one-parameter strong-interaction limit functional, and we show that the resulting method reproduces the correlation energy of the uniform electron gas over a wide range of densities. When applied to subsets of the GMTKN55 thermochemistry database, OSMI is more accurate on average than MP2 and nonempirical density functionals. Most notably, OSMI provides excellent predictions of the barrier heights we tested, with average errors of less than 2 kcal mol-1. Finally, we find that OSMI improves the trade-off between fractional spin and fractional charge errors for bond dissociation curves compared to DFT and MP2. The fact that OSMI provides a good description of molecular systems and the uniform electron gas, while also maintaining low self-interaction error and size-consistency, suggests that it could provide a framework for studying heterogeneous chemical systems.
Keywords:
GAUSSIAN-BASIS SETS
CORRELATED MOLECULAR CALCULATIONS
STRONG-INTERACTION LIMIT
MOLLER-PLESSET THEORY
CORRELATION-ENERGY
CORE-VALENCE
COMPUTATIONAL CHEMISTRY
PERTURBATION-THEORY
GROUND-STATE
ATOMS

Journal

Journal of Chemical Theory and Computation cover
Journal of Chemical Theory and Computation
IF:
5.5
Papers:
1.1W
Citations:
5.4W

Organization

S
Simons Foundation
Scholars:
200
Papers: 135
Citations: 1.1K