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A Variational Approach to London Dispersion Interactions without Density Distortion.

ABSTRACT: We introduce a class of variational wave functions that captures the long-range interaction between neutral systems (atoms and molecules) without changing the diagonal of the density matrix of each monomer. The corresponding energy optimization yields explicit expressions for the dispersion coefficients in terms of the ground-state pair densities of the isolated systems, providing a clean theoretical framework to build new approximations in several contexts. As the individual monomer densities are kept fixed, we can also unambiguously assess the effect of the density distortion on London dispersion interactions; for example, we obtain virtually exact dispersion coefficients between two hydrogen atoms up to C₁₀ and relative errors below 0.2% in other simple cases.

SUBMITTER: Kooi DP

PROVIDER: S-EPMC6452420 | biostudies-literature | 2019 Apr

REPOSITORIES: biostudies-literature

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A Variational Approach to London Dispersion Interactions without Density Distortion.

Kooi Derk P DP Gori-Giorgi Paola P

The journal of physical chemistry letters 20190320 7

We introduce a class of variational wave functions that captures the long-range interaction between neutral systems (atoms and molecules) without changing the diagonal of the density matrix of each monomer. The corresponding energy optimization yields explicit expressions for the dispersion coefficients in terms of the ground-state pair densities of the isolated systems, providing a clean theoretical framework to build new approximations in several contexts. As the individual monomer densities a ...[more]

PMID: 30865464

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