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Modeling the adsorption of short alkanes in the zeolite SSZ-13 using "van der Waals" DFT exchange correlation functionals: Understanding the advantages and limitations of such functionals

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JOURNAL OF CHEMICAL PHYSICS 2014年第15期140卷 154105-154105页

作者： Goeltl, Florian Sautet, Philippe Univ Lyon CNRS Ecole Normale Super Lyon Lab Chim F-69342 Lyon 07 France

The inclusion of non-local interactions is one of the large challenges in density functional theory. Very promising methods are the vdW-DF2 and BEEF-vdW functionals, which combine a semi-local approximation for exchange interactions and a non-local correlation expression. In this work we apply those functionals to model the adsorption of short alkanes in the zeolite SSZ-13. Even though results for energetics are improved with respect to other vdW-DF based methods, we still find a comparatively large error compared to high-level calculations. These errors result from approximations in the determination of the dielectric function and of the van der Waals kernel. The insights presented in this work will help to understand the performance not only of vdW-DF2 and BEEF-vdW, but all vdW-DF based functionals in various chemically or physically important systems. (C) 2014 AIP Publishing LLC.

关键词： Adsorption Zeolites Density functional theory exchange correlation functionals Methane

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Water on BN doped benzene: A hard test for exchange-correlation functionals and the impact of exact exchange on weak binding

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JOURNAL OF CHEMICAL PHYSICS 2014年第18期141卷 18C530-18C530页

作者： Al-Hamdani, Yasmine S. Alfe, Dario von Lilienfeld, O. Anatole Michaelides, Angelos Thomas Young Ctr London WC1H 0AH England London Ctr Nanotechnol London WC1H 0AH England UCL Dept Chem London WC1H 0AJ England UCL Dept Earth Sci London WC1E 6BT England Univ Basel Inst Phys Chem Dept Chem CH-4056 Basel Switzerland Argonne Natl Labs Lemont IL 60439 USA

Density functional theory (DFT) studies of weakly interacting complexes have recently focused on the importance of van der Waals dispersion forces, whereas the role of exchange has received far less attention. Here, by exploiting the subtle binding between water and a boron and nitrogen doped benzene derivative (1,2-azaborine) we show how exact exchange can alter the binding conformation within a complex. Benchmark values have been calculated for three orientations of the water monomer on 1,2-azaborine from explicitly correlated quantum chemical methods, and we have also used diffusion quantum Monte Carlo. For a host of popular DFT exchange-correlation functionals we show that the lack of exact exchange leads to the wrong lowest energy orientation of water on 1,2-azaborine. As such, we suggest that a high proportion of exact exchange and the associated improvement in the electronic structure could be needed for the accurate prediction of physisorption sites on doped surfaces and in complex organic molecules. Meanwhile to predict correct absolute interaction energies an accurate description of exchange needs to be augmented by dispersion inclusive functionals, and certain non-local van der Waals functionals (optB88- and optB86b-vdW) perform very well for absolute interaction energies. Through a comparison with water on benzene and borazine (B3N3H6) we show that these results could have implications for the interaction of water with doped graphene surfaces, and suggest a possible way of tuning the interaction energy. (C) 2014 Author(s). All article content, except where otherwise noted, is licensed under a Creative Commons Attribution 3.0 Unported License.

关键词： Water energy interactions Weak interactions Doping exchange correlation functionals Graphene

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A comparison of three DFT exchange-correlation functionals and two basis sets for the prediction of the conformation distribution of hydrated polyglycine

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JOURNAL OF CHEMICAL PHYSICS 2021年第9期155卷 094104-094104页

作者： Yuan, Ying Wang, Feng Univ Arkansas Dept Chem & Biochem Fayetteville AR 72701 USA

The performance of three density functional theory (DFT) exchange-correlation functionals, namely, Perdew-Burke-Ernzerhof (PBE), BP86, and B3LYP, in predicting conformational distributions of a hydrated glycine peptide is tested with two different basis sets in the framework of adaptive force matching (AFM). The conformational distributions yielded the free energy profiles of the DFT functional and basis set combinations. Unlike traditional validations of potential energy and structural parameters, our approach allows the free energy of DFT to be validated. When compared to experimental distributions, the def2-TZVP basis set provides better agreement than a slightly trimmed aug-cc-pVDZ basis set. B3LYP is shown to be better than BP86 and PBE. The glycine model fitted against B3LYP-D3(BJ) with the def2-TZVP basis set is the most accurate and named the AFM2021 model for glycine. The AFM2021 glycine model provides better agreement with experimental J-coupling constants than C36m and ff14SB, although the margin is very small when compared to C36m. Our previously published alanine model is also refitted with the slightly simplified AFM2021 energy expression. This work shows good promise of AFM for developing force fields for a range of proteinogenic peptides using only DFT as reference.

关键词： exchange correlation functionals correlation-consistent basis sets Amino acid Chemical bonding Potential energy surfaces Peptides Nuclear magnetic resonance Scholarly publishing Density functional theory Coupling constants

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Bandgap of two-dimensional materials: Thorough assessment of modern exchange-correlation functionals

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JOURNAL OF CHEMICAL PHYSICS 2021年第10期155卷 104103-9页

作者： Tran, Fabien Doumont, Jan Kalantari, Leila Blaha, Peter Rauch, Tomas Borlido, Pedro Botti, Silvana Marques, Miguel A. L. Patra, Abhilash Jana, Subrata Samal, Prasanjit Vienna Univ Technol Inst Mat Chem Getreidemarkt 9-165 TC A-1060 Vienna Austria Friedrich Schiller Univ Jena Inst Festkorpertheorie & Opt Max Wien Pl 1 D-07743 Jena Germany European Theoret Spect Facil Max Wien Pl 1 D-07743 Jena Germany Martin Luther Univ Halle Wittenberg Inst Phys D-06099 Halle Germany HBNI Natl Inst Sci Educ & Res Sch Phys Sci Bhubaneswar 752050 India

The density-functional theory (DFT) approximations that are the most accurate for the calculation of bandgap of bulk materials are hybrid functionals, such as HSE06, the modified Becke-Johnson (MBJ) potential, and the GLLB-SC potential. More recently, generalized gradient approximations (GGAs), such as HLE16, or meta-GGAs, such as (m)TASK, have also proven to be quite accurate for the bandgap. Here, the focus is on two-dimensional (2D) materials and the goal is to provide a broad overview of the performance of DFT functionals by considering a large test set of 298 2D systems. The present work is an extension of our recent studies [T. Rauch, M. A. L. Marques, and S. Botti, Phys. Rev. B 101, 245163 (2020);Patra et al., J. Phys. Chem. C 125, 11206 (2021)]. Due to the lack of experimental results for the bandgap of 2D systems, G(0)W(0) results were taken as reference. It is shown that the GLLB-SC potential and mTASK functional provide the bandgaps that are the closest to G(0)W(0). Following closely, the local MBJ potential has a pretty good accuracy that is similar to the accuracy of the more expensive hybrid functional HSE06. (c) 2021 Author(s). All article content, except where otherwise noted, is licensed under a Creative Commons Attribution (CC BY) license (http://***/licenses/by/4.0/).

关键词： Hybrid density functional calculations exchange correlation functionals Band gap 2D materials Density functional theory GW method

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Massively parallel linear-scaling Hartree-Fock exchange and hybrid exchange-correlation functionals with plane wave basis set accuracy

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JOURNAL OF CHEMICAL PHYSICS 2021年第22期155卷 224106-224106页

作者： Dziedzic, Jacek Womack, James C. Ali, Rozh Skylaris, Chris-Kriton Univ Southampton Sch Chem Southampton SO17 1BJ Hants England Gdansk Univ Technol Fac Appl Phys & Math PL-80233 Gdansk Poland Univ Bristol Adv Comp Res Ctr Res Software Engn Bristol BS1 5QD Avon England Charmo Univ Coll Med & Appl Sci Appl Phys Dept Chamchamal 46023 Sulaimania Iraq

We extend our linear-scaling approach for the calculation of Hartree-Fock exchange energy using localized in situ optimized orbitals [Dziedzic et al., J. Chem. Phys. 139, 214103 (2013)] to leverage massive parallelism. Our approach has been implemented in the onetep (Order-N Electronic Total Energy Package) density functional theory framework, which employs a basis of non-orthogonal generalized Wannier functions (NGWFs) to achieve linear scaling with system size while retaining controllable near-complete-basis-set accuracy. For the calculation of Hartree-Fock exchange, we use a resolution-of-identity approach, where an auxiliary basis set of truncated spherical waves is used to fit products of NGWFs. The fact that the electrostatic potential of spherical waves (SWs) is known analytically, combined with the use of a distance-based cutoff for exchange interactions, leads to a calculation cost that scales linearly with the system size. Our new implementation, which we describe in detail, combines distributed memory parallelism (using the message passing interface) with shared memory parallelism (OpenMP threads) to efficiently utilize numbers of central processing unit cores comparable to, or exceeding, the number of atoms in the system. We show how the use of multiple time-memory trade-offs substantially increases performance, enabling our approach to achieve superlinear strong parallel scaling in many cases and excellent, although sublinear, parallel scaling otherwise. We demonstrate that in scenarios with low available memory, which preclude or limit the use of time-memory trade-offs, the performance degradation of our algorithm is graceful. We show that, crucially, linear scaling with system size is maintained in all cases. We demonstrate the practicability of our approach by performing a set of fully converged production calculations with a hybrid functional on large imogolite nanotubes up to over 1400 atoms. We finish with a brief study of how the employed approxi

关键词： Special Topics: Beyond GGA Total Energies for Solids and Surfaces Topics Hybrid density functional calculations Message passing interface Electrostatics Basis sets exchange correlation functionals OpenMP exchange interactions Wannier functions.

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Construction of self-interaction-corrected exchange-correlation functionals within the correlation factor approach

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JOURNAL OF CHEMICAL PHYSICS 2019年第19期151卷 194102-194102页

作者： Wang, Rodrigo Zhou, Yongxi Ernzerhof, Matthias Univ Montreal Dept Chim CP 6128 Succursale A Montreal PQ H3C 3J7 Canada

To model the exchange-correlation hole rho(XC)(r, u) of Kohn-Sham theory, we employ the correlation factor ansatz, which has recently been developed in our group. In this ansatz, rho(XC)(r, u) is written as a product of the correlation factor f(C)(r, u) and an exchange-hole model rho(X)(r, u), i.e., rho(XC)(r, u) = f(C)(r, u)rho(X)(r, u). In particular, we address the one-electron, self-interaction error and introduce a modified correlation factor model where f(C)(r, u) is constructed such that it reduces identically to one in localized one-electron regions of a many-electron system. This self-interaction corrected exchange-correlation hole is then used to generate the corresponding exchange-correlation energy functional. The new functional is implemented into a Kohn-Sham program and assessed by calculating various molecular properties. We find that, overall, a significant improvement is obtained compared to previous versions of the correlation factor model. Published under license by AIP Publishing.

关键词： Molecular properties exchange correlation functionals Dissociation energy Hybrid density functional calculations correlation energy Density functional theory Many electron systems exchange interactions Kohn-Sham equation

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Communication: Near-locality of exchange and correlation density functionals for 1-and 2-electron systems

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JOURNAL OF CHEMICAL PHYSICS 2016年第19期144卷 191101-191101页

作者： Sun, Jianwei Perdew, John P. Yang, Zenghui Peng, Haowei Temple Univ Dept Phys Philadelphia PA 19122 USA Temple Univ Dept Chem Philadelphia PA 19122 USA

The uniform electron gas and the hydrogen atom play fundamental roles in condensed matter physics and quantum chemistry. The former has an infinite number of electrons uniformly distributed over the neutralizing positively charged background, and the latter only one electron bound to the proton. The uniform electron gas was used to derive the local spin density approximation to the exchange-correlation functional that undergirds the development of the Kohn-Sham density functional theory. We show here that the ground-state exchange-correlation energies of the hydrogen atom and many other 1- and 2-electron systems are modeled surprisingly well by a different local spin density approximation (LSDA0). LSDA0 is constructed to satisfy exact constraints but agrees surprisingly well with the exact results for a uniform two-electron density in a finite, curved three-dimensional space. We also apply LSDA0 to excited or noded 1-electron densities, where it works less well. Furthermore, we show that the localization of the exact exchange hole for a 1- or 2-electron ground state can be measured by the ratio of the exact exchange energy to its optimal lower bound. Published by AIP Publishing.

关键词： Ground states exchange correlation functionals Local density approximations Protons Electron correlation calculations

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Design of exchange-correlation functionals through the correlation factor approach

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JOURNAL OF CHEMICAL PHYSICS 2015年第14期143卷 144102-144102页

作者： Precechtelova, Jana Pavlikova Bahmann, Hilke Kaupp, Martin Ernzerhof, Matthias Univ Montreal Dept Chim Montreal PQ H3C 3J7 Canada Tech Univ Berlin Sekr C7 Inst Chem Theoret Chem Quantenchem D-10623 Berlin Germany

The correlation factor model is developed in which the spherically averaged exchange-correlation hole of Kohn-Sham theory is factorized into an exchange hole model and a correlation factor. The exchange hole model reproduces the exact exchange energy per particle. The correlation factor is constructed in such a manner that the exchange-correlation energy correctly reduces to exact exchange in the high density and rapidly varying limits. Four different correlation factor models are presented which satisfy varying sets of physical constraints. Three models are free from empirical adjustments to experimental data, while one correlation factor model draws on one empirical parameter. The correlation factor models are derived in detail and the resulting exchange-correlation holes are analyzed. Furthermore, the exchange-correlation energies obtained from the correlation factor models are employed to calculate total energies, atomization energies, and barrier heights. It is shown that accurate, non-empirical functionals can be constructed building on exact exchange. Avenues for further improvements are outlined as well. (C) 2015 AIP Publishing LLC.

关键词： exchange correlation functionals Electron correlation calculations Rotational correlation time Electron gas Total energy calculations

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Computational modeling and characterization of X-Bi (X = B, Al, Ga, In) compounds: Prospective optoelectronic materials for infrared/near infra applications

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COMPUTATIONAL MATERIALS SCIENCE 2016年 114卷 40-46页

作者： Rahim, Nor Ashwani Abdul Ahmed, R. Ul Haq, Bakhtiar Mohamad, Mazmira Shaari, A. Ali, N. Goumri-Said, Souraya Univ Teknol Malaysia Fac Sci Dept Phys Utm Johor Bahru 81310 Johor Malaysia Sungkyunkwan Univ Dept Phys Suwon 440746 South Korea Georgia Inst Technol Sch Chem & Biochem Atlanta GA 30332 USA Georgia Inst Technol Ctr Organ Photon & Elect Atlanta GA 30332 USA Al Faisal Univ Dept Phys Coll Sci POB 50927 Riyadh 11533 Saudi Arabia

III-V compounds containing heavy Bi anion are distinguished from remaining III-V family in terms of their narrower electronic energy gap and potential application for infrared/near infra devices. In the present work, modeling of X-Bi (X = B, Al, Ga and In) compounds and the investigations pertaining to their physical properties were carried out using density functional theory (DFT) based full-potential linearized augmented plane wave plus local orbital, FP-L(APW + lo) approach within various functional of the exchange correlation potentials. The calculated total energies of X-Bi in various geometries reveal that zinc blende phase is the stable ground state structure of BBi, AlBi and GaBi. However, InBi adapts PbO phase at ground state. It was also found that BBi exhibit an electronic structure with an indirect energy gap. However, AlBi, GaBi and InBi are semi-metallic with a narrower or zero band gap. The calculation of the optical properties show that among X-Bi compounds, BBi was found to exhibit higher absorption coefficient values, lower reflectivity and refractive index, enlightening their potential for infrared/near infra devices and other optoelectronic applications as well. (C) 2015 Elsevier B.V. All rights reserved.

关键词： DFT FP-LAPW plus lo exchange correlation functionals Electronic structure Optical properties

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TD-DFT study on the charge-transfer excitations of anions possessing double or triple bonds

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COMPUTATIONAL AND THEORETICAL CHEMISTRY 2013年 1014卷 49-55页

作者： Kozlowska, Justyna Wielgus, Malgorzata Bartkowiak, Wojciech Wroclaw Univ Technol Inst Phys & Theoret Chem Theoret Chem Grp PL-50370 Wroclaw Poland

Time-dependent density functional theory calculations, employing generalized gradient approximation (GGA), global hybrids (GH) as well as range-separated hybrid (RSH) functionals, have been carried out to determine the electronic excitation energies of p-nitrophenolate anions. The gas-phase electronic spectra of the investigated compounds were compared with recently reported experimental data (M.-B.S. Kirketerp et al., ChemPhysChem, 11 (2010) 2495-2498). The best agreement with experimental data was achieved with the pure functionals. (C) 2013 Elsevier B.V. All rights reserved.

关键词： TD-DFT exchange correlation functionals Charge-transfer Anion Excitation energy Gas-phase spectrum

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