Article
Chemistry, Multidisciplinary
Katarzyna Pernal, Michal Hapka
Summary: Range-separated multiconfigurational density functional theory (RS MC-DFT) combines density functional and wavefunction theories by partitioning the electron interaction operator and modeling with different methods. RS MC-DFT aims to increase versatility and accuracy of methods while reducing computational cost. Variants of RS MC-DFT can be divided into single-determinant-based and multideterminantal approaches for describing electron correlation energy. Applications include ground-state properties of molecules and noncovalent interactions, as well as time-dependent linear-response theory and direct approaches to excited states. Advantages of RS MC-DFT over conventional DFT and ab initio methods are assessed for each area of application.
WILEY INTERDISCIPLINARY REVIEWS-COMPUTATIONAL MOLECULAR SCIENCE
(2022)
Article
Chemistry, Physical
Viki Kumar Prasad, Alberto Otero-de-la-Roza, Gino A. DiLabio
Summary: Density functional theory (DFT) is widely used for modeling noncovalent interactions and thermochemistry. This article presents three new DFT methods that combine appropriate functionals, relatively large basis sets, and atom-centered potentials (ACPs) for improved accuracy and computational efficiency in predicting chemical properties.
JOURNAL OF CHEMICAL THEORY AND COMPUTATION
(2022)
Article
Chemistry, Physical
Abhishek Raghav, Ryo Maezono, Kenta Hongo, Sandro Sorella, Kousuke Nakano
Summary: In this study, accurate atomization energy calculations for 55 molecules in the Gaussian-2 (G2) set were performed using lattice regularized diffusion Monte Carlo (LRDMC). The effectiveness of the flexible Jastrow correlated antisymmetrized geminal power with singlet correlation (JsAGPs) ansatz for atomization energy calculations and electronic structure simulations was demonstrated. LRDMC atomization energies obtained using the JsAGPs ansatz reached chemical accuracy for many molecules and were accurate within 5 kcal/mol for most other molecules.
JOURNAL OF CHEMICAL THEORY AND COMPUTATION
(2023)
Article
Chemistry, Physical
Chandler Greenwell, Jan Rezac, Gregory J. O. Beran
Summary: A spin-component-scaled, dispersion-corrected MP2 model (SCS-MP2D) is proposed to address the limitations of MP2 in describing dispersion interactions and reaction thermochemistry. Experimental results show that SCS-MP2D considerably improves the accuracy of MP2 and is comparable in accuracy and computational cost to state-of-the-art density functionals.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2022)
Article
Chemistry, Physical
Naveen K. Dandu, Rajeev S. Assary, Paul C. Redfern, Logan Ward, Ian Foster, Larry A. Curtiss
Summary: G4MP2 theory has higher errors when applied to larger organic molecules, which is due to the higher-level correction not taking into account the element and bond type dependence. By introducing an atom-specific correction, G4MP2A method shows comparable accuracy to G4 theory with lower computational cost. The G4MP2A method also improves ionization potentials and electron affinities, and can be used in machine learning methods for predicting molecular energies.
JOURNAL OF PHYSICAL CHEMISTRY A
(2022)
Article
Chemistry, Physical
Viki Kumar Prasad, Alberto Otero-de-la-Roza, Gino A. DiLabio
Summary: In this study, a new low-cost quantum mechanical method using atom-centered potentials (ACPs) was developed to model large molecular systems. Machine learning regression technique was utilized to train and validate the ACP-corrected methods. The proposed ACP-corrected methods showed comparable performance to complete basis set density functional theory at a much lower cost, and could improve the description of covalent and noncovalent bond geometries.
JOURNAL OF CHEMICAL THEORY AND COMPUTATION
(2022)
Article
Chemistry, Physical
E. Bremond, M. Rodriguez-Mayorga, A. J. Perez-Jimenez, C. Adamo, J. C. Sancho-Garcia
Summary: In this study, we have updated the Quadratic Integrand Double-Hybrid (QIDH) model by incorporating the nonempirical r(2)SCAN meta-generalized gradient approximation exchange-correlation functional. The new model shows a high level of accuracy and competitiveness in various types of non-covalent interactions.
JOURNAL OF CHEMICAL PHYSICS
(2023)
Article
Chemistry, Physical
Subrata Jana, John M. M. Herbert
Summary: This article examines methods for calculating X-ray absorption spectra using a constrained core hole, which may contain a fractional electron. These methods are based on Slater's transition concept and generalize it by using Kohn-Sham orbital energies to determine core-to-valence excitation energies. The tested methods achieve robust convergence by avoiding promoting electrons beyond the lowest unoccupied molecular orbital. The best-case accuracy of these methods is found to be 0.3-0.4 eV with respect to experiment for K-edge transition energies. Higher-lying near-edge transitions have larger absolute errors, but these can be reduced below 1 eV by introducing an empirical shift based on a charge-neutral transition-potential method combined with specific functionals like SCAN, SCAN0, or B3LYP. This procedure allows for obtaining an entire excitation spectrum from a single fractional-electron calculation, without the need for state-by-state calculations based on ground-state density functional theory. The shifted transition-potential approach proposed in this study is particularly useful for simulating transient spectroscopies and in complex systems where excited-state Kohn-Sham calculations are challenging.
JOURNAL OF CHEMICAL THEORY AND COMPUTATION
(2023)
Article
Chemistry, Physical
Golokesh Santra, Emmanouil Semidalas, Nisha Mehta, Amir Karton, Jan M. L. Martin
Summary: The S66x8 noncovalent interactions benchmark has been re-evaluated using different methods and considering different basis sets and truncation error corrections. The study found that the LNO-CCSD(T) method performs well under very tight criteria, but struggles with complex counterpoise corrections. In contrast, the PNO-LCCSD(T) method performs best with counterpoise corrections.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2022)
Article
Chemistry, Physical
Kimberly J. Daas, Derk P. Kooi, Nina C. Peters, Eduardo Fabiano, Fabio Della Sala, Paola Gori-Giorgi, Stefan Vuckovic
Summary: Noncovalent interactions are crucial in various fields and a methodology for improving pure quantum-chemical simulations of these interactions has been proposed. The methodology combines interpolation, regularization, and spin-scaling strategies to enhance accuracy and competitiveness for noncovalent interactions.
JOURNAL OF PHYSICAL CHEMISTRY LETTERS
(2023)
Article
Materials Science, Multidisciplinary
Xin-Qiang Wang, Mingqing Liu, Lijuan Jia, Pei-Guang Yan, Wei-Chao Jiang
Summary: The study investigates the relationship between laser intensity and high-order harmonic generation (HHG) in ZnO theoretically. It is found that the intensities of lower-order harmonics, contributed mainly by intraband electron oscillation, increase monotonously with light intensity. However, the intensities of higher-order harmonics, dominated by interband electron-hole recollision, oscillate with light intensity. Models of intraband and interband electronic dynamics are built to examine the effect of laser intensity on individual single-order harmonics that are far from the band gap.
Article
Chemistry, Physical
Yi Xie, Daniel G. A. Smith, C. David Sherrill
Summary: This study presents an implementation of a symmetry-adapted perturbation theory algorithm based on density functional theory, utilizing density-fitting treatment of hybrid exchange-correlation kernels for describing monomers with hybrid functionals. The algorithm shows improved numerical stability and computational efficiency, performing well for systems with up to 3000 basis functions.
JOURNAL OF CHEMICAL PHYSICS
(2022)
Article
Chemistry, Physical
Nicholas A. Szaro, Mubarak Bello, Charles H. Fricke, Olajide H. Bamidele, Andreas Heyden
Summary: This study compares the accuracy of DFT and RPA methods for the ethane dehydrogenation reaction on Pt(111), finding that PBE and RPBE without dispersion correction can closely model the energy calculated by RPA. However, RPA fails to accurately describe the gas phase energy as unsaturation and chain-length increase in hydrocarbons. RPBE has the best accuracy-to-cost ratio, suggesting that RPA may not be superior to RPBE or BEEF-vdW.
JOURNAL OF PHYSICAL CHEMISTRY LETTERS
(2023)
Article
Chemistry, Physical
Ernest R. Davidson, Joseph Vincent Ortiz, Viktor N. Staroverov
Summary: The CAS extended Koopmans theorem (EKT) method is a special case of EKT, equivalent to the CI procedure involving all hole-state configurations derived from the active space of the reference wavefunction. The first ionization energy predicted by the EKT is not exact, but can approach the full CI result with arbitrary precision.
JOURNAL OF CHEMICAL PHYSICS
(2021)
Article
Health Care Sciences & Services
Carlos A. F. Santos, Gislene R. Amirato, Alessandro F. Jacinto, Ana V. Pedrosa, Adriana Caldo-Silva, Antonio R. Sampaio, Nuno Pimenta, Juliana M. B. Santos, Alberto Pochini, Andre L. L. Bachi
Summary: This study aimed to assess the safety and usefulness of vertical jump tests in evaluating physical performance in older women. The results showed that vertical jump tests are safe and accurate, making them useful for monitoring age-related muscle performance loss in robust older women.
Article
Chemistry, Physical
Oliver J. Backhouse, Max Nusspickel, George H. Booth
JOURNAL OF CHEMICAL THEORY AND COMPUTATION
(2020)
Article
Physics, Multidisciplinary
Kiel T. Williams, Yuan Yao, Jia Li, Li Chen, Hao Shi, Mario Motta, Chunyao Niu, Ushnish Ray, Sheng Guo, Robert J. Anderson, Junhao Li, Lan Nguyen Tran, Chia-Nan Yeh, Bastien Mussard, Sandeep Sharma, Fabien Bruneval, Mark van Schilfgaarde, George H. Booth, Garnet Kin-Lic Chan, Shiwei Zhang, Emanuel Gull, Dominika Zgid, Andrew Millis, Cyrus J. Umrigar, Lucas K. Wagner
Article
Physics, Multidisciplinary
Gerard McCaul, Christopher Orthodoxou, Kurt Jacobs, George H. Booth, Denys Bondar
PHYSICAL REVIEW LETTERS
(2020)
Article
Chemistry, Physical
Qiming Sun, Xing Zhang, Samragni Banerjee, Peng Bao, Marc Barbry, Nick S. Blunt, Nikolay A. Bogdanov, George H. Booth, Jia Chen, Zhi-Hao Cui, Janus Juul Eriksen, Yang Gao, Sheng Guo, Jan Hermann, Matthew R. Hermes, Kevin Koh, Peter Koval, Susi Lehtola, Zhendong Li, Junzi Liu, Narbe Mardirossian, James D. McClain, Mario Motta, Bastien Mussard, Hung Q. Pham, Artem Pulkin, Wirawan Purwanto, Paul J. Robinson, Enrico Ronca, Elvira Sayfutyarova, Maximilian Scheurer, Henry F. Schurkus, James E. T. Smith, Chong Sun, Shi-Ning Sun, Shiv Upadhyay, Lucas K. Wagner, Xiao Wang, Alec White, James Daniel Whitfield, Mark J. Williamson, Sebastian Wouters, Jun Yang, Jason M. Yu, Tianyu Zhu, Timothy C. Berkelbach, Sandeep Sharma, Alexander Sokolov, Garnet Kin-Lic Chan
JOURNAL OF CHEMICAL PHYSICS
(2020)
Article
Chemistry, Physical
Kai Guther, Robert J. Anderson, Nick S. Blunt, Nikolay A. Bogdanov, Deidre Cleland, Nike Dattani, Werner Dobrautz, Khaldoon Ghanem, Peter Jeszenszki, Niklas Liebermann, Giovanni Li Manni, Alexander Y. Lozovoi, Hongjun Luo, Dongxia Ma, Florian Merz, Catherine Overy, Markus Rampp, Pradipta Kumar Samanta, Lauretta R. Schwarz, James J. Shepherd, Simon D. Smart, Eugenio Vitale, Oskar Weser, George H. Booth, Ali Alavi
JOURNAL OF CHEMICAL PHYSICS
(2020)
Article
Chemistry, Physical
Yannic Rath, Aldo Glielmo, George H. Booth
JOURNAL OF CHEMICAL PHYSICS
(2020)
Article
Chemistry, Physical
Kai Guther, Aron J. Cohen, Hongjun Luo, Ali Alavi
Summary: In this study, the application of similarity-transformed full configuration interaction quantum Monte Carlo based on the transcorrelated Hamiltonian in predicting the binding curve of the beryllium dimer has been demonstrated. By effectively addressing dynamic correlation beyond the basis set, accurate energies close to the complete basis set limit can be obtained with moderate basis sets and computational effort. The role of the Jastrow factor, its functional form, and potential sources for size consistency errors are discussed, leading to Jastrow forms that allow for high accuracy calculations of the vibrational spectrum of the beryllium dimer.
JOURNAL OF CHEMICAL PHYSICS
(2021)
Article
Chemistry, Physical
Thomas Schraivogel, Aron J. Cohen, Ali Alavi, Daniel Kats
Summary: In this study, transcorrelated coupled cluster and distinguishable cluster methods are introduced, where the Hamiltonian is transformed using a Jastrow factor in first quantization leading to improved basis set convergence and accuracy. The coupled cluster with singles and doubles equations on the transformed Hamiltonian shows superior performance compared to conventional and explicitly correlated methods. Approaches for approximating three-body integrals are also suggested and evaluated.
JOURNAL OF CHEMICAL PHYSICS
(2021)
Article
Chemistry, Physical
Werner Dobrautz, Aron J. Cohen, Ali Alavi, Emmanuel Giner
Summary: This study investigates the performance of a new transcorrelated (TC) approach based on a single-parameter correlation factor for systems involving multiple electrons, showing promising results for computing accurate ground state total energies. The use of the single-parameter correlation factor yields satisfactory results compared to more sophisticated factors in certain basis sets, demonstrating its potential for efficient calculations in quantum chemistry.
JOURNAL OF CHEMICAL PHYSICS
(2022)
Review
Physics, Multidisciplinary
Jules Tilly, Hongxiang Chen, Shuxiang Cao, Dario Picozzi, Kanav Setia, Ying Li, Edward Grant, Leonard Wossnig, Ivan Rungger, George H. Booth, Jonathan Tennyson
Summary: The variational quantum eigensolver (VQE) is a method used to compute the ground state energy of a Hamiltonian, which is important in quantum chemistry and condensed matter physics. It has the advantage of being able to model complex wavefunctions in polynomial time, making it a promising application for quantum computing. However, there are still many open questions regarding optimization, quantum noise, and other challenges, which require further research and exploration.
PHYSICS REPORTS-REVIEW SECTION OF PHYSICS LETTERS
(2022)
Article
Physics, Multidisciplinary
Yannic Rath, George H. Booth
Summary: This paper introduces a quantum Gaussian process state, which is obtained by statistically inferring the wave function supported by a dataset of unentangled product states. The state can be condensed into a compact and expressive parametric form, and it shows competitive or superior variational flexibility compared to established alternatives.
PHYSICAL REVIEW RESEARCH
(2022)
Article
Materials Science, Multidisciplinary
Charles J. C. Scott, George H. Booth
Summary: Extended Density Matrix Embedding Theory (EDMET) overcomes the limitations of traditional embedding methods by self-consistently treating local two-body physics. It accurately describes phase transitions and dynamics, and can provide good agreement with experimental results for ab initio systems.
Article
Optics
Hongxiang Chen, Max Nusspickel, Jules Tilly, George H. Booth
Summary: This research demonstrates how to use the variational quantum eigensolver (VQE) algorithm to calculate the dynamic correlation function of quantum systems and describe their linear response characteristics, which can converge on the frequency axis. The method is not affected by gate depth and can be used to compute correlated systems with frequency dynamics.
Article
Physics, Multidisciplinary
L. Wright, F. Barratt, J. Dborin, G. H. Booth, A. G. Green
Summary: Inspired by thermalization, this method harnesses insensitivity to details of the bath and replaces post-selection operations with tracing operations, leading to improved performance on current quantum computers involving superconducting circuits.
PHYSICAL REVIEW RESEARCH
(2021)
Article
Physics, Multidisciplinary
Aldo Glielmo, Yannic Rath, Gabor Csanyi, Alessandro De Vita, George H. Booth