1
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Zhang Q, Wang RS, Wang L. Neural canonical transformations for vibrational spectra of molecules. J Chem Phys 2024; 161:024103. [PMID: 38979703 DOI: 10.1063/5.0209255] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2024] [Accepted: 06/19/2024] [Indexed: 07/10/2024] Open
Abstract
The behavior of polyatomic molecules around their equilibrium positions can be regarded as that of quantum-coupled anharmonic oscillators. Solving the corresponding Schrödinger equations enables the interpretation or prediction of the experimental spectra of molecules. In this study, we developed a novel approach for solving the excited states of anharmonic vibrational systems. The normal coordinates of the molecules are transformed into new coordinates through a normalizing flow parameterized by a neural network. This facilitates the construction of a set of orthogonal many-body variational wavefunctions. This methodology has been validated on an exactly solvable 64-dimensional coupled harmonic oscillator, yielding numerical results with a relative error of 10-6. The neural canonical transformations are also applied to calculate the energy levels of two specific molecules, acetonitrile (CH3CN) and ethylene oxide (C2H4O). These molecules involve 12 and 15 vibrational modes, respectively. A key advantage of this approach is its flexibility concerning the potential energy surface, as it requires no specific form. Furthermore, this method can be readily implemented on large-scale distributed computing platforms, making it easy to extend to investigating complex vibrational structures.
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Affiliation(s)
- Qi Zhang
- Beijing National Laboratory for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
| | - Rui-Si Wang
- Beijing National Laboratory for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Lei Wang
- Beijing National Laboratory for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
- Songshan Lake Materials Laboratory, Dongguan, Guangdong 523808, China
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2
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Spencer RJ, Zhanserkeev AA, Yang EL, Steele RP. The Near-Sightedness of Many-Body Interactions in Anharmonic Vibrational Couplings. J Am Chem Soc 2024; 146:15376-15392. [PMID: 38771156 DOI: 10.1021/jacs.4c03198] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/22/2024]
Abstract
Couplings between vibrational motions are driven by electronic interactions, and these couplings carry special significance in vibrational energy transfer, multidimensional spectroscopy experiments, and simulations of vibrational spectra. In this investigation, the many-body contributions to these couplings are analyzed computationally in the context of clathrate-like alkali metal cation hydrates, including Cs+(H2O)20, Rb+(H2O)20, and K+(H2O)20, using both analytic and quantum-chemistry potential energy surfaces. Although the harmonic spectra and one-dimensional anharmonic spectra depend strongly on these many-body interactions, the mode-pair couplings were, perhaps surprisingly, found to be dominated by one-body effects, even in cases of couplings to low-frequency modes that involved the motion of multiple water molecules. The origin of this effect was traced mainly to geometric distortion within water monomers and cancellation of many-body effects in differential couplings, and the effect was also shown to be agnostic to the identity of the ion. These outcomes provide new understanding of vibrational couplings and suggest the possibility of improved computational methods for the simulation of infrared and Raman spectra.
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Affiliation(s)
- Ryan J Spencer
- Department of Chemistry and Henry Eyring Center for Theoretical Chemistry, University of Utah, Salt Lake City, Utah 84112, United States
| | - Asylbek A Zhanserkeev
- Department of Chemistry and Henry Eyring Center for Theoretical Chemistry, University of Utah, Salt Lake City, Utah 84112, United States
| | - Emily L Yang
- Department of Chemistry and Henry Eyring Center for Theoretical Chemistry, University of Utah, Salt Lake City, Utah 84112, United States
| | - Ryan P Steele
- Department of Chemistry and Henry Eyring Center for Theoretical Chemistry, University of Utah, Salt Lake City, Utah 84112, United States
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3
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Glaser N, Baiardi A, Reiher M. Flexible DMRG-Based Framework for Anharmonic Vibrational Calculations. J Chem Theory Comput 2023; 19:9329-9343. [PMID: 38060309 PMCID: PMC10753801 DOI: 10.1021/acs.jctc.3c00902] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2023] [Revised: 10/16/2023] [Accepted: 10/23/2023] [Indexed: 12/08/2023]
Abstract
We present a novel formulation of the vibrational density matrix renormalization group (vDMRG) algorithm tailored to strongly anharmonic molecules described by general, high-dimensional model representations of potential energy surfaces. For this purpose, we extend the vDMRG framework to support vibrational Hamiltonians expressed in the so-called n-mode second-quantization formalism. The resulting n-mode vDMRG method offers full flexibility with respect to both the functional form of the PES and the choice of the single-particle basis set. We leverage this framework to apply, for the first time, vDMRG based on an anharmonic modal basis set optimized with the vibrational self-consistent field algorithm on an on-the-fly constructed PES. We also extend the n-mode vDMRG framework to include excited-state-targeting algorithms in order to efficiently calculate anharmonic transition frequencies. We demonstrate the capabilities of our novel n-mode vDMRG framework for methyloxirane, a challenging molecule with 24 coupled vibrational modes.
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Affiliation(s)
- Nina Glaser
- Department of Chemistry
and Applied Biosciences, ETH Zurich, Vladimir-Prelog-Weg 2, 8093 Zurich, Switzerland
| | - Alberto Baiardi
- Department of Chemistry
and Applied Biosciences, ETH Zurich, Vladimir-Prelog-Weg 2, 8093 Zurich, Switzerland
| | - Markus Reiher
- Department of Chemistry
and Applied Biosciences, ETH Zurich, Vladimir-Prelog-Weg 2, 8093 Zurich, Switzerland
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4
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Yang EL, Talbot JJ, Spencer RJ, Steele RP. Pitfalls in the n-mode representation of vibrational potentials. J Chem Phys 2023; 159:204104. [PMID: 38010326 DOI: 10.1063/5.0176612] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2023] [Accepted: 10/19/2023] [Indexed: 11/29/2023] Open
Abstract
Simulations of anharmonic vibrational motion rely on computationally expedient representations of the governing potential energy surface. The n-mode representation (n-MR)-effectively a many-body expansion in the space of molecular vibrations-is a general and efficient approach that is often used for this purpose in vibrational self-consistent field (VSCF) calculations and correlated analogues thereof. In the present analysis, a lack of convergence in many VSCF calculations is shown to originate from negative and unbound potentials at truncated orders of the n-MR expansion. For cases of strong anharmonic coupling between modes, the n-MR can both dip below the true global minimum of the potential surface and lead to effective single-mode potentials in VSCF that do not correspond to bound vibrational problems, even for bound total potentials. The present analysis serves mainly as a pathology report of this issue. Furthermore, this insight into the origin of VSCF non-convergence provides a simple, albeit ad hoc, route to correct the problem by "painting in" the full representation of groups of modes that exhibit these negative potentials at little additional computational cost. Somewhat surprisingly, this approach also reasonably approximates the results of the next-higher n-MR order and identifies groups of modes with particularly strong coupling. The method is shown to identify and correct problematic triples of modes-and restore SCF convergence-in two-mode representations of challenging test systems, including the water dimer and trimer, as well as protonated tropine.
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Affiliation(s)
- Emily L Yang
- Department of Chemistry, The University of Utah, 315 S 1400 E, Salt Lake City, Utah 84112, USA
- Henry Eyring Center for Theoretical Chemistry, The University of Utah, Salt Lake City, Utah 84112, USA
| | - Justin J Talbot
- Department of Chemistry, University of California-Berkeley, 420 Latimer Hall, Berkeley, California 94720, USA
| | - Ryan J Spencer
- Department of Chemistry, The University of Utah, 315 S 1400 E, Salt Lake City, Utah 84112, USA
- Henry Eyring Center for Theoretical Chemistry, The University of Utah, Salt Lake City, Utah 84112, USA
| | - Ryan P Steele
- Department of Chemistry, The University of Utah, 315 S 1400 E, Salt Lake City, Utah 84112, USA
- Henry Eyring Center for Theoretical Chemistry, The University of Utah, Salt Lake City, Utah 84112, USA
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5
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Zhanserkeev AA, Yang EL, Steele RP. Accelerating Anharmonic Spectroscopy Simulations via Local-Mode, Multilevel Methods. J Chem Theory Comput 2023; 19:5572-5585. [PMID: 37555634 DOI: 10.1021/acs.jctc.3c00589] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/10/2023]
Abstract
Ab initio computer simulations of anharmonic vibrational spectra provide nuanced insight into the vibrational behavior of molecules and complexes. The computational bottleneck in such simulations, particularly for ab initio potentials, is often the generation of mode-coupling potentials. Focusing specifically on two-mode couplings in this analysis, the combination of a local-mode representation and multilevel methods is demonstrated to be particularly symbiotic. In this approach, a low-level quantum chemistry method is employed to predict the pairwise couplings that should be included at the target level of theory in vibrational self-consistent field (and similar) calculations. Pairs that are excluded by this approach are "recycled" at the low level of theory. Furthermore, because this low-level pre-screening will eventually become the computational bottleneck for sufficiently large chemical systems, distance-based truncation is applied to these low-level predictions without substantive loss of accuracy. This combination is demonstrated to yield sub-wavenumber fidelity with reference vibrational transitions when including only a small fraction of target-level couplings; the overhead of predicting these couplings, particularly when employing distance-based, local-mode cutoffs, is a trivial added cost. This combined approach is assessed on a series of test cases, including ethylene, hexatriene, and the alanine dipeptide. Vibrational self-consistent field (VSCF) spectra were obtained with an RI-MP2/cc-pVTZ potential for the dipeptide, at approximately a 5-fold reduction in computational cost. Considerable optimism for increased accelerations for larger systems and higher-order couplings is also justified, based on this investigation.
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Affiliation(s)
- Asylbek A Zhanserkeev
- Department of Chemistry and Henry Eyring Center for Theoretical Chemistry, University of Utah, 315 South 1400 East, Salt Lake City, Utah 84112, United States
| | - Emily L Yang
- Department of Chemistry and Henry Eyring Center for Theoretical Chemistry, University of Utah, 315 South 1400 East, Salt Lake City, Utah 84112, United States
| | - Ryan P Steele
- Department of Chemistry and Henry Eyring Center for Theoretical Chemistry, University of Utah, 315 South 1400 East, Salt Lake City, Utah 84112, United States
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6
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Woo J, Kim WY, Choi S. System-Specific Separable Basis Based on Tucker Decomposition: Application to Density Functional Calculations. J Chem Theory Comput 2022; 18:2875-2884. [PMID: 35437014 PMCID: PMC9098162 DOI: 10.1021/acs.jctc.1c01263] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
![]()
For fast density
functional calculations, a suitable basis that
can accurately represent the orbitals within a reasonable number of
dimensions is essential. Here, we propose a new type of basis constructed
from Tucker decomposition of a finite-difference (FD) Hamiltonian
matrix, which is intended to reflect the system information implied
in the Hamiltonian matrix and satisfies orthonormality and separability
conditions. By introducing the system-specific separable basis, the
computation time for FD density functional calculations for seven
two- and three-dimensional periodic systems was reduced by a factor
of 2–71 times, while the errors in both the atomization energy
per atom and the band gap were limited to less than 0.1 eV. The accuracy
and speed of the density functional calculations with the proposed
basis can be systematically controlled by adjusting the rank size
of Tucker decomposition.
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Affiliation(s)
- Jeheon Woo
- Department of Chemistry, KAIST, 291 Daehak-ro, Yuseong-gu, Daejeon 34141, Republic of Korea
| | - Woo Youn Kim
- Department of Chemistry, KAIST, 291 Daehak-ro, Yuseong-gu, Daejeon 34141, Republic of Korea
| | - Sunghwan Choi
- National Institute of Supercomputing and Networking, Korea Institute of Science and Technology Information, Daejeon 34141, Republic of Korea
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7
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Changala PB. Vibronic mean-field and perturbation theory for Jahn-Teller and pseudo-Jahn-Teller molecules. Mol Phys 2021. [DOI: 10.1080/00268976.2021.1962556] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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8
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Madsen NK, Jensen RB, Christiansen O. Calculating vibrational excitation energies using tensor-decomposed vibrational coupled-cluster response theory. J Chem Phys 2021; 154:054113. [DOI: 10.1063/5.0037240] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Affiliation(s)
- Niels Kristian Madsen
- Department of Chemistry, University of Aarhus, Langelandsgade 140, DK–8000 Aarhus C, Denmark
| | - Rasmus Berg Jensen
- Department of Chemistry, University of Aarhus, Langelandsgade 140, DK–8000 Aarhus C, Denmark
| | - Ove Christiansen
- Department of Chemistry, University of Aarhus, Langelandsgade 140, DK–8000 Aarhus C, Denmark
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9
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Hansen MB, Madsen NK, Christiansen O. Extended vibrational coupled cluster: Stationary states and dynamics. J Chem Phys 2020; 153:044133. [DOI: 10.1063/5.0015413] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- Mads Bøttger Hansen
- Department of Chemistry, Aarhus University, Langelandsgade 140, DK-8000 Aarhus C, Denmark
| | - Niels Kristian Madsen
- Department of Chemistry, Aarhus University, Langelandsgade 140, DK-8000 Aarhus C, Denmark
| | - Ove Christiansen
- Department of Chemistry, Aarhus University, Langelandsgade 140, DK-8000 Aarhus C, Denmark
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10
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Ollitrault PJ, Baiardi A, Reiher M, Tavernelli I. Hardware efficient quantum algorithms for vibrational structure calculations. Chem Sci 2020; 11:6842-6855. [PMID: 32874524 PMCID: PMC7448527 DOI: 10.1039/d0sc01908a] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2020] [Accepted: 06/02/2020] [Indexed: 11/21/2022] Open
Abstract
We introduce a framework for the calculation of ground and excited state energies of bosonic systems suitable for near-term quantum devices and apply it to molecular vibrational anharmonic Hamiltonians. Our method supports generic reference modal bases and Hamiltonian representations, including the ones that are routinely used in classical vibrational structure calculations. We test different parametrizations of the vibrational wavefunction, which can be encoded in quantum hardware, based either on heuristic circuits or on the bosonic Unitary Coupled Cluster Ansatz. In particular, we define a novel compact heuristic circuit and demonstrate that it provides a good compromise in terms of circuit depth, optimization costs, and accuracy. We evaluate the requirements, number of qubits and circuit depth, for the calculation of vibrational energies on quantum hardware and compare them with state-of-the-art classical vibrational structure algorithms for molecules with up to seven atoms.
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Affiliation(s)
- Pauline J Ollitrault
- IBM Quantum , IBM Research - Zurich , Säumerstrasse 4 , 8803 Rüschlikon , Switzerland .
- Laboratory of Physical Chemistry , ETH Zürich , Vladimir-Prelog-Weg 2 , 8093 Zürich , Switzerland .
| | - Alberto Baiardi
- Laboratory of Physical Chemistry , ETH Zürich , Vladimir-Prelog-Weg 2 , 8093 Zürich , Switzerland .
| | - Markus Reiher
- Laboratory of Physical Chemistry , ETH Zürich , Vladimir-Prelog-Weg 2 , 8093 Zürich , Switzerland .
| | - Ivano Tavernelli
- IBM Quantum , IBM Research - Zurich , Säumerstrasse 4 , 8803 Rüschlikon , Switzerland .
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11
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Klinting EL, Christiansen O, König C. Toward Accurate Theoretical Vibrational Spectra: A Case Study for Maleimide. J Phys Chem A 2020; 124:2616-2627. [DOI: 10.1021/acs.jpca.9b11915] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Affiliation(s)
| | - Ove Christiansen
- Department of Chemistry, Aarhus University, DK-8000 Aarhus C, Denmark
| | - Carolin König
- Institute of Physical Chemistry, Kiel University, Max-Eyth-Straße 1, D-24118 Kiel, Germany
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12
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Pouchan C. Quantum molecular dynamic approach to modeling the vibrational spectra of propynenitrile and its 1:1 complexes with water. COMPUT THEOR CHEM 2019. [DOI: 10.1016/j.comptc.2019.06.004] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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13
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Schmitz G, Christiansen O. Assessment of the overlap metric in the context of RI-MP2 and atomic batched tensor decomposed MP2. Chem Phys Lett 2018. [DOI: 10.1016/j.cplett.2018.04.014] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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14
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Madsen NK, Godtliebsen IH, Losilla SA, Christiansen O. Tensor-decomposed vibrational coupled-cluster theory: Enabling large-scale, highly accurate vibrational-structure calculations. J Chem Phys 2018; 148:024103. [DOI: 10.1063/1.5001569] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
| | | | | | - Ove Christiansen
- Department of Chemistry, Aarhus University, 8000 Aarhus C, Denmark
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15
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Thomas PS, Carrington T. An intertwined method for making low-rank, sum-of-product basis functions that makes it possible to compute vibrational spectra of molecules with more than 10 atoms. J Chem Phys 2017; 146:204110. [PMID: 28571348 PMCID: PMC5451316 DOI: 10.1063/1.4983695] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2017] [Accepted: 05/05/2017] [Indexed: 11/14/2022] Open
Abstract
We propose a method for solving the vibrational Schrödinger equation with which one can compute spectra for molecules with more than ten atoms. It uses sum-of-product (SOP) basis functions stored in a canonical polyadic tensor format and generated by evaluating matrix-vector products. By doing a sequence of partial optimizations, in each of which the factors in a SOP basis function for a single coordinate are optimized, the rank of the basis functions is reduced as matrix-vector products are computed. This is better than using an alternating least squares method to reduce the rank, as is done in the reduced-rank block power method. Partial optimization is better because it speeds up the calculation by about an order of magnitude and allows one to significantly reduce the memory cost. We demonstrate the effectiveness of the new method by computing vibrational spectra of two molecules, ethylene oxide (C2H4O) and cyclopentadiene (C5H6), with 7 and 11 atoms, respectively.
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Affiliation(s)
- Phillip S Thomas
- Chemistry Department, Queen's University, Kingston, Ontario K7L 3N6, Canada
| | - Tucker Carrington
- Chemistry Department, Queen's University, Kingston, Ontario K7L 3N6, Canada
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16
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Schmitz G, Madsen NK, Christiansen O. Atomic-batched tensor decomposed two-electron repulsion integrals. J Chem Phys 2017; 146:134112. [DOI: 10.1063/1.4979571] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- Gunnar Schmitz
- Department of Chemistry, Aarhus Universitet, DK-8000 Aarhus, Denmark
| | | | - Ove Christiansen
- Department of Chemistry, Aarhus Universitet, DK-8000 Aarhus, Denmark
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17
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Madsen NK, Godtliebsen IH, Christiansen O. Efficient algorithms for solving the non-linear vibrational coupled-cluster equations using full and decomposed tensors. J Chem Phys 2017; 146:134110. [DOI: 10.1063/1.4979498] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- Niels K. Madsen
- Department of Chemistry, Aarhus University, 8000 Aarhus C, Denmark
| | | | - Ove Christiansen
- Department of Chemistry, Aarhus University, 8000 Aarhus C, Denmark
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18
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Ostrowski L, Ziegler B, Rauhut G. Tensor decomposition in potential energy surface representations. J Chem Phys 2016; 145:104103. [DOI: 10.1063/1.4962368] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Affiliation(s)
- Lukas Ostrowski
- Institut für Theoretische Chemie, Universität Stuttgart, Pfaffenwaldring 55, 70569 Stuttgart, Germany
| | - Benjamin Ziegler
- Institut für Theoretische Chemie, Universität Stuttgart, Pfaffenwaldring 55, 70569 Stuttgart, Germany
| | - Guntram Rauhut
- Institut für Theoretische Chemie, Universität Stuttgart, Pfaffenwaldring 55, 70569 Stuttgart, Germany
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19
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Garnier R, Odunlami M, Le Bris V, Bégué D, Baraille I, Coulaud O. Adaptive vibrational configuration interaction (A-VCI):A posteriorierror estimation to efficiently compute anharmonic IR spectra. J Chem Phys 2016; 144:204123. [DOI: 10.1063/1.4952414] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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20
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Godtliebsen IH, Hansen MB, Christiansen O. Tensor decomposition techniques in the solution of vibrational coupled cluster response theory eigenvalue equations. J Chem Phys 2015; 142:024105. [DOI: 10.1063/1.4905160] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
| | | | - Ove Christiansen
- Department of Chemistry, Aarhus University, 8000 Aarhus C, Denmark
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