Correction to “Solid Oganesson via a Many-Body Interaction Expansion Based on Relativistic Coupled-Cluster Theory and from Plane-Wave Relativistic Density Functional Theory”

Thermally feasible decomposition pathways of formamide (FM) in the presence of vanadium VO(X4Σ−) and titanium TiO(X3Δ) monoxides are determined using density functional theory (the BP86 functional) and coupled-cluster theory (CCSD(T)) computations with large basis sets.

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Predicting band gaps of semiconductors with quantum chemistry

EPJ Web of Conferences ◽

10.1051/epjconf/202024600006 ◽

2020 ◽

Vol 246 ◽

pp. 00006

Author(s):

Anneke Dittmer

Keyword(s):

Density Functional Theory ◽

Quantum Chemistry ◽

Band Gap ◽

Organic Semiconductors ◽

Density Functional ◽

Band Gaps ◽

Coupled Cluster ◽

Functional Theory ◽

Coupled Cluster Theory ◽

Electrostatic Embedding

The following article gives a brief introduction to quantum chemistry and its application to the prediction of band gaps of inorganic and organic semiconductors. Two important quantum chemistry concepts —Density Functional Theory (DFT) and Coupled Cluster Theory (CC)— are shortly explained. These two concepts are used to calculate the optical and the transport band gap of a set of semiconductors modelled with an electrostatic embedding approach.

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Elevating Density Functional Theory to Chemical Accuracy for Water Simulations through a Density-Corrected Many-Body Formalism

10.33774/chemrxiv-2021-hstgf-v3 ◽

2021 ◽

Author(s):

Saswata Dasgupta ◽

Eleftherios Lambros ◽

John Perdew ◽

Francesco Paesani

Keyword(s):

Density Functional Theory ◽

Density Functional ◽

Water Clusters ◽

Potential Energy Function ◽

Data Driven ◽

Coupled Cluster ◽

Many Body ◽

Functional Theory ◽

Dynamics Simulations ◽

Body Potential

Density functional theory (DFT) has been extensively used to model the properties of water. Albeit maintaining a good balance between accuracy and efficiency, no density functional has so far achieved the degree of accuracy necessary to correctly predict the properties of water across the entire phase diagram. Here, we present density-corrected SCAN (DC-SCAN) calculations for water which, minimizing density-driven errors, elevate the accuracy of the SCAN functional to that of “gold standard” coupled-cluster theory. Building upon the accuracy of DC-SCAN within a many-body formalism, we introduce a data-driven many-body potential energy function, MB-SCAN(DC), that quantitatively reproduces coupled cluster reference values for interaction, binding, and individual many-body energies of water clusters. Importantly, molecular dynamics simulations carried out with MB-SCAN(DC) also reproduce the properties of liquid water, which thus demonstrates that MB-SCAN(DC) is effectively the first DFT-based model that correctly describes water from the gas to the liquid phase.

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Highly Accurate Many-Body Potentials for Simulations of N2O5 in Water: Benchmarks, Development, and Validation

10.26434/chemrxiv.13613678 ◽

2021 ◽

Author(s):

Vinicius Cruzeiro ◽

Eleftherios Lambros ◽

Marc Riera ◽

Ronak Roy ◽

Francesco Paesani ◽

...

Keyword(s):

Density Functional Theory ◽

Atmospheric Chemistry ◽

Short Range ◽

Density Functional ◽

Coupled Cluster ◽

Many Body ◽

Functional Theory ◽

High Level ◽

Three Body ◽

Many Body Interactions

<div><div><div><p>Dinitrogen pentoxide (N2O5) is an important intermediate in the atmospheric chemistry of nitrogen oxides. Although there has been much research, the processes that govern the physical interactions between N2O5 and water are still not fully understood at a molecular level. Gaining quantitative insight from computer simulations requires going beyond the accuracy of classical force fields, while accessing length scales and time scales that are out of reach for high-level quantum chemical approaches. To this end we present the development of MB-nrg many-body potential energy functions for simulations of N2O5 in water. This MB-nrg model is based on electronic structure calculations at the coupled cluster level of theory and is compatible with the successful MB-pol model for water. It provides a physically correct description of long-range many-body interactions in combination with an explicit representation of up to three-body short-range interactions in terms of multidimensional permutationally invariant polynomials. In order to further investigate the importance of the underlying interactions in the model, a TTM-nrg model was also devised. TTM- nrg is a more simplistic representation that contains only two-body short-range interactions represented through Born-Mayer functions. In this work an active learning approach was employed to efficiently build representative training sets of monomer, dimer and trimer structures, and benchmarks are presented to determine the accuracy of our new models in comparison to a range of density functional theory methods. By assessing binding curves, distortion energies of N2O5, and interaction energies in clusters of N2O5 and water, we evaluate the importance of two-body and three-body short-range potentials. The results demonstrate that our MB-nrg model has high accuracy with respect to the coupled cluster reference, outperforms current density functional theory models, and thus enables highly accurate simulations of N2O5 in aqueous environments.</p></div></div></div>

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