1
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Wu CH, Magers DB, Harding LB, Klippenstein SJ, Allen WD. Reaction Profiles and Kinetics for Radical-Radical Hydrogen Abstraction via Multireference Coupled Cluster Theory. J Chem Theory Comput 2020; 16:1511-1525. [PMID: 32073856 DOI: 10.1021/acs.jctc.9b00966] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Radical-radical abstractions in hydrocarbon oxidation chemistry are disproportionation reactions that are generally exothermic with little or no barrier yet are underappreciated and poorly studied. Such challenging multireference electronic structure problems are tackled here using the recently developed state-specific multireference coupled cluster methods Mk-MRCCSD and Mk-MRCCSD(T), as well as the companion perturbation theory Mk-MRPT2 and the established MRCISD, MRCISD+Q, and CASPT2 approaches. Reaction paths are investigated for five prototypes involving radical-radical hydrogen abstraction: H + BeH → H2+ Be, H + NH2 → H2 + NH, CH3 + C2H5 → CH4 + C2H4, H + C2H5 → H2 + C2H4, and H + HCO → H2 + CO. Full configuration interaction (FCI) benchmark computations for the H + BeH, H + NH2, and H + HCO reactions prove that Mk-MRCCSD(T) provides superior accuracy for the interaction energies in the entrance channel, with mean absolute errors less than 0.3 kcal mol-1 and percentage deviations less than 10% over the fragment separations of relevance to kinetics. To facilitate combustion studies, energetics for the CH3 + C2H5, H + C2H5, and H + HCO reactions were computed at each level of theory with correlation-consistent basis sets (cc-pVXZ, X = T, Q, 5) and extrapolated to the complete basis set (CBS) limit. These CBS energies were coupled with CASPT2 projected vibrational frequencies along a minimum energy path to obtain rate constants for these three reactions. The rigorous Mk-MRCCSD(T)/CBS results demonstrate unequivocally that these three reactions proceed with no barrier in the entrance channel, contrary to some earlier predictions. Mk-MRCCSD(T) also reveals that the economical CASPT2 method performs well for large interfragment separations but may deteriorate substantially at shorter distances.
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Affiliation(s)
- Chia-Hua Wu
- Center for Computational Quantum Chemistry and Department of Chemistry, University of Georgia, Athens, Georgia 30602, United States
| | - D Brandon Magers
- Center for Computational Quantum Chemistry and Department of Chemistry, University of Georgia, Athens, Georgia 30602, United States.,Department of Chemistry and Physics, Belhaven University, Jackson, Mississippi 39202, United States
| | - Lawrence B Harding
- Chemical Sciences and Engineering Division, Argonne National Laboratory, Lemont, Illinois 60439, United States
| | - Stephen J Klippenstein
- Chemical Sciences and Engineering Division, Argonne National Laboratory, Lemont, Illinois 60439, United States
| | - Wesley D Allen
- Center for Computational Quantum Chemistry and Department of Chemistry, University of Georgia, Athens, Georgia 30602, United States
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2
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Kállay M, Nagy PR, Mester D, Rolik Z, Samu G, Csontos J, Csóka J, Szabó PB, Gyevi-Nagy L, Hégely B, Ladjánszki I, Szegedy L, Ladóczki B, Petrov K, Farkas M, Mezei PD, Ganyecz Á. The MRCC program system: Accurate quantum chemistry from water to proteins. J Chem Phys 2020; 152:074107. [DOI: 10.1063/1.5142048] [Citation(s) in RCA: 152] [Impact Index Per Article: 38.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Affiliation(s)
- Mihály Kállay
- Department of Physical Chemistry and Materials Science, Budapest University of Technology and Economics, P.O. Box 91, H-1521 Budapest, Hungary
| | - Péter R. Nagy
- Department of Physical Chemistry and Materials Science, Budapest University of Technology and Economics, P.O. Box 91, H-1521 Budapest, Hungary
| | - Dávid Mester
- Department of Physical Chemistry and Materials Science, Budapest University of Technology and Economics, P.O. Box 91, H-1521 Budapest, Hungary
| | - Zoltán Rolik
- Department of Physical Chemistry and Materials Science, Budapest University of Technology and Economics, P.O. Box 91, H-1521 Budapest, Hungary
| | - Gyula Samu
- Department of Physical Chemistry and Materials Science, Budapest University of Technology and Economics, P.O. Box 91, H-1521 Budapest, Hungary
| | - József Csontos
- Department of Physical Chemistry and Materials Science, Budapest University of Technology and Economics, P.O. Box 91, H-1521 Budapest, Hungary
| | - József Csóka
- Department of Physical Chemistry and Materials Science, Budapest University of Technology and Economics, P.O. Box 91, H-1521 Budapest, Hungary
| | - P. Bernát Szabó
- Department of Physical Chemistry and Materials Science, Budapest University of Technology and Economics, P.O. Box 91, H-1521 Budapest, Hungary
| | - László Gyevi-Nagy
- Department of Physical Chemistry and Materials Science, Budapest University of Technology and Economics, P.O. Box 91, H-1521 Budapest, Hungary
| | - Bence Hégely
- Department of Physical Chemistry and Materials Science, Budapest University of Technology and Economics, P.O. Box 91, H-1521 Budapest, Hungary
| | - István Ladjánszki
- Department of Physical Chemistry and Materials Science, Budapest University of Technology and Economics, P.O. Box 91, H-1521 Budapest, Hungary
| | - Lóránt Szegedy
- Department of Physical Chemistry and Materials Science, Budapest University of Technology and Economics, P.O. Box 91, H-1521 Budapest, Hungary
| | - Bence Ladóczki
- Department of Physical Chemistry and Materials Science, Budapest University of Technology and Economics, P.O. Box 91, H-1521 Budapest, Hungary
| | - Klára Petrov
- Department of Physical Chemistry and Materials Science, Budapest University of Technology and Economics, P.O. Box 91, H-1521 Budapest, Hungary
| | - Máté Farkas
- Department of Physical Chemistry and Materials Science, Budapest University of Technology and Economics, P.O. Box 91, H-1521 Budapest, Hungary
| | - Pál D. Mezei
- Department of Physical Chemistry and Materials Science, Budapest University of Technology and Economics, P.O. Box 91, H-1521 Budapest, Hungary
| | - Ádám Ganyecz
- Department of Physical Chemistry and Materials Science, Budapest University of Technology and Economics, P.O. Box 91, H-1521 Budapest, Hungary
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3
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Miyagawa K, Kawakami T, Suzuki Y, Isobe H, Shoji M, Yamanaka S, Okumura M, Nakajima T, Yamaguchi K. Domain-based local pair natural orbital CCSD(T) calculations of strongly correlated electron systems: Examination of dynamic equilibrium models based on multiple intermediates in S1 state of photosystem II. Mol Phys 2019. [DOI: 10.1080/00268976.2019.1666171] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Affiliation(s)
- K. Miyagawa
- Institute for Scientific and Industrial Research, Osaka University, Osaka 567-0047, Japan
| | - T. Kawakami
- Graduate School of Science, Osaka University, Toyonaka 560-0043, Japan
- RIKEN Center for Computational Science, Kobe, Hyogo 650-0047, Japan
| | - Y. Suzuki
- Graduate School of Science, Osaka University, Toyonaka 560-0043, Japan
| | - H. Isobe
- Graduate School of Natural Science and Technology, Okayama University, Okayama 700-8530, Japan
| | - M. Shoji
- Center of Computational Sciences, Tsukuba University, Tsukuba, Ibaraki 305-8577, Japan
| | - S. Yamanaka
- Graduate School of Science, Osaka University, Toyonaka 560-0043, Japan
| | - M. Okumura
- Graduate School of Science, Osaka University, Toyonaka 560-0043, Japan
| | - T. Nakajima
- RIKEN Center for Computational Science, Kobe, Hyogo 650-0047, Japan
| | - K. Yamaguchi
- Institute for Scientific and Industrial Research, Osaka University, Osaka 567-0047, Japan
- RIKEN Center for Computational Science, Kobe, Hyogo 650-0047, Japan
- Insitute for Nanoscience Design, Osaka University, Toyonaka 560-0043, Japan
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Husch T, Freitag L, Reiher M. Calculation of Ligand Dissociation Energies in Large Transition-Metal Complexes. J Chem Theory Comput 2018; 14:2456-2468. [PMID: 29595973 DOI: 10.1021/acs.jctc.8b00061] [Citation(s) in RCA: 52] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
The accurate calculation of ligand dissociation (or equivalently, ligand binding) energies is crucial for computational coordination chemistry. Despite its importance, obtaining accurate ab initio reference data is difficult, and density-functional methods of uncertain reliability are chosen for feasibility reasons. Here, we consider advanced coupled-cluster and multiconfigurational approaches to reinvestigate our WCCR10 set of 10 gas-phase ligand dissociation energies [ J. Chem. Theory Comput. 2014, 10, 3092]. We assess the potential multiconfigurational character of all molecules involved in these reactions with a multireference diagnostic [ Mol. Phys. 2017, 115, 2110] in order to determine where single-reference coupled-cluster approaches can be applied. For some reactions of the WCCR10 set, large deviations of density-functional results including semiclassical dispersion corrections from experimental reference data had been observed. This puzzling observation deserves special attention here, and we tackle the issue (i) by comparing to ab initio data that comprise dispersion effects on a rigorous first-principles footing and (ii) by a comparison of density-functional approaches that model dispersion interactions in various ways. For two reactions, species exhibiting nonnegligible static electron correlation were identified. These two reactions represent hard problems for electronic structure methods and also for multireference perturbation theories. However, most of the ligand dissociation reactions in WCCR10 do not exhibit static electron correlation effects, and hence, we may choose standard single-reference coupled-cluster approaches to compare with density-functional methods. For WCCR10, the Minnesota M06-L functional yielded the smallest mean absolute deviation of 13.2 kJ mol-1 out of all density functionals considered (PBE, BP86, BLYP, TPSS, M06-L, PBE0, B3LYP, TPSSh, and M06-2X) without additional dispersion corrections in comparison to the coupled-cluster results, and the PBE0-D3 functional produced the overall smallest mean absolute deviation of 4.3 kJ mol-1. The agreement of density-functional results with coupled-cluster data increases significantly upon inclusion of any type of dispersion correction. It is important to emphasize that different density-functional schemes available for this purpose perform equally well. The coupled-cluster dissociation energies, however, deviate from experimental results on average by 30.3 kJ mol-1. Possible reasons for these deviations are discussed.
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Affiliation(s)
- Tamara Husch
- Laboratorium für Physikalische Chemie , ETH Zürich , Vladimir-Prelog-Weg 2 , 8093 Zürich , Switzerland
| | - Leon Freitag
- Laboratorium für Physikalische Chemie , ETH Zürich , Vladimir-Prelog-Weg 2 , 8093 Zürich , Switzerland
| | - Markus Reiher
- Laboratorium für Physikalische Chemie , ETH Zürich , Vladimir-Prelog-Weg 2 , 8093 Zürich , Switzerland
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Aoto YA, Köhn A. Internally contracted multireference coupled-cluster theory in a multistate framework. J Chem Phys 2016; 144:074103. [DOI: 10.1063/1.4941604] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Affiliation(s)
- Yuri Alexandre Aoto
- Institut für Theoretische Chemie, Universität Stuttgart, Pfaffenwaldring 55, D-70569 Stuttgart, Germany
| | - Andreas Köhn
- Institut für Theoretische Chemie, Universität Stuttgart, Pfaffenwaldring 55, D-70569 Stuttgart, Germany
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Demel O, Pittner J, Neese F. A Local Pair Natural Orbital-Based Multireference Mukherjee’s Coupled Cluster Method. J Chem Theory Comput 2015; 11:3104-14. [DOI: 10.1021/acs.jctc.5b00334] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Ondřej Demel
- J.
Heyrovský Institute of Physical Chemistry, v.v.i., Academy of Sciences of the Czech Republic, Dolejškova 3, 18223 Prague 8, Czech Republic
| | - Jiří Pittner
- J.
Heyrovský Institute of Physical Chemistry, v.v.i., Academy of Sciences of the Czech Republic, Dolejškova 3, 18223 Prague 8, Czech Republic
| | - Frank Neese
- Max Planck Institute
of Chemical Energy Conversion, 45470 Mülheim an der Ruhr, Germany
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Banik S, Ravichandran L, Brabec J, Hubač I, Kowalski K, Pittner J. Iterative universal state selective correction for the Brillouin-Wigner multireference coupled-cluster theory. J Chem Phys 2015; 142:114106. [PMID: 25796230 DOI: 10.1063/1.4914311] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
As a further development of the previously introduced a posteriori Universal State-Selective (USS) corrections [K. Kowalski, J. Chem. Phys. 134, 194107 (2011); J. Brabec et al., ibid. 136, 124102 (2012)], we suggest an iterative form of the USS correction by means of correcting effective Hamiltonian matrix elements. We also formulate USS corrections via the left Bloch equations. The convergence of the USS corrections with excitation level towards the full configuration interaction (FCI) limit is also investigated. Various forms of the USS and simplified diagonal USS corrections at the singles and doubles and perturbative triple levels are numerically assessed on several model systems and on the ozone and tetramethyleneethane molecules. It is shown that the iterative USS correction can successfully replace the previously developed a posteriori Brillouin-Wigner coupled cluster size-extensivity correction, while it is not sensitive to intruder states and performs well also in other cases when the a posteriori one fails, like, e.g., for the asymmetric vibration mode of ozone.
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Affiliation(s)
- Subrata Banik
- J. Heyrovský Institute of Physical Chemistry, Academy of Sciences of the Czech Republic, CZ-18223 Prague 8, Czech Republic
| | - Lalitha Ravichandran
- J. Heyrovský Institute of Physical Chemistry, Academy of Sciences of the Czech Republic, CZ-18223 Prague 8, Czech Republic
| | - Jiří Brabec
- Computational Research Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA
| | - Ivan Hubač
- Department of Chemical Physics, Faculty of Mathematics and Physics, Comenius University, 84215 Bratislava, Slovakia
| | - Karol Kowalski
- William R. Wiley Environmental Molecular Sciences Laboratory, Battelle, Pacific Northwest National Laboratory, K8-91, P.O. Box 999, Richland, Washington 99352, USA
| | - Jiří Pittner
- J. Heyrovský Institute of Physical Chemistry, Academy of Sciences of the Czech Republic, CZ-18223 Prague 8, Czech Republic
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8
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Banerjee D, Ghosh A, Chattopadhyay S, Ghosh P, Chaudhuri RK. Revisiting the ‘cis-effect’ in 1,2-difluoro derivatives of ethylene and diazene usingab initiomultireference methods. Mol Phys 2014. [DOI: 10.1080/00268976.2014.938710] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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9
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Aspects of size extensivity in unitary group adapted multi-reference coupled cluster theories: the role of cumulant decomposition of spin-free reduced density matrices. Theor Chem Acc 2014. [DOI: 10.1007/s00214-014-1522-5] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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10
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Stein T, Henderson TM, Scuseria GE. Seniority zero pair coupled cluster doubles theory. J Chem Phys 2014; 140:214113. [DOI: 10.1063/1.4880819] [Citation(s) in RCA: 125] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Affiliation(s)
- Tamar Stein
- Department of Chemistry, Rice University, Houston, Texas 77251, USA
| | - Thomas M. Henderson
- Department of Chemistry, Rice University, Houston, Texas 77251, USA
- Department of Physics and Astronomy, Rice University, Houston, Texas 77251, USA
| | - Gustavo E. Scuseria
- Department of Chemistry, Rice University, Houston, Texas 77251, USA
- Department of Physics and Astronomy, Rice University, Houston, Texas 77251, USA
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11
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Samanta PK, Mukherjee D, Hanauer M, Köhn A. Excited states with internally contracted multireference coupled-cluster linear response theory. J Chem Phys 2014; 140:134108. [DOI: 10.1063/1.4869719] [Citation(s) in RCA: 31] [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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12
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Bhaskaran-Nair K, Kowalski K. Bridging single and multireference coupled cluster theories with universal state selective formalism. J Chem Phys 2013; 138:204114. [DOI: 10.1063/1.4806768] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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13
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Jeszenszki P, Surján PR, Szabados Á. Spin-adaptation and redundancy in state-specific multireference perturbation theory. J Chem Phys 2013; 138:124110. [DOI: 10.1063/1.4795436] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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14
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Shen J, Piecuch P. Merging Active-Space and Renormalized Coupled-Cluster Methods via the CC(P;Q) Formalism, with Benchmark Calculations for Singlet–Triplet Gaps in Biradical Systems. J Chem Theory Comput 2012; 8:4968-88. [DOI: 10.1021/ct300762m] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Jun Shen
- Department of Chemistry, Michigan State University,
East Lansing, Michigan 48824, United States
| | - Piotr Piecuch
- Department of Chemistry, Michigan State University,
East Lansing, Michigan 48824, United States
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15
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Köhn A, Hanauer M, Mück LA, Jagau TC, Gauss J. State-specific multireference coupled-cluster theory. WILEY INTERDISCIPLINARY REVIEWS-COMPUTATIONAL MOLECULAR SCIENCE 2012. [DOI: 10.1002/wcms.1120] [Citation(s) in RCA: 83] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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16
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Small DW, Head-Gordon M. A fusion of the closed-shell coupled cluster singles and doubles method and valence-bond theory for bond breaking. J Chem Phys 2012; 137:114103. [DOI: 10.1063/1.4751485] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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17
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Jagau TC, Gauss J. Linear-response theory for Mukherjee's multireference coupled-cluster method: Static and dynamic polarizabilities. J Chem Phys 2012; 137:044115. [DOI: 10.1063/1.4734308] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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18
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Maitra R, Sinha D, Mukherjee D. Unitary group adapted state-specific multi-reference coupled cluster theory: Formulation and pilot numerical applications. J Chem Phys 2012; 137:024105. [DOI: 10.1063/1.4731341] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Mahapatra US, Chattopadhyay S. Diagnosis of the performance of the state-specific multireference coupled-cluster method with different truncation schemes. J Comput Chem 2012; 33:1285-303. [PMID: 22419455 DOI: 10.1002/jcc.22960] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2011] [Revised: 02/06/2012] [Accepted: 02/07/2012] [Indexed: 11/06/2022]
Abstract
We have tested the linked version of a iterative (partial) triples correction for the Jeziorski-Monkhorst ansatz based state-specific multireference coupled cluster (SS-MRCC) approach with singles and doubles (SD) excitations [abbreviated as SS-MRCCSDT-1a and SS-MRCCSDT-1a+d]. The assessments of SS-MRCCSDT-1a and SS-MRCCSDT-1a+d schemes have been performed on the ground potential energy surface (PES) of P4, Li(2),Be(2) systems which demand the MR description, and on study of the excitation energy between the ground and first excited state for P4 system. Illustrations in the isomerization of cyclobutadiene also show the power of the schemes. One of the designed features of the SS-MRCCSDT-n methods introduced here is that they do not require storage of the triples amplitudes. In the entire range of geometries, we found a definite improvement provided by SS-MRCC with SDT-1a and SDT-1a+d schemes over the standard SD one. In the nondegenerate regions of PES, the closeness of the performance of the single-reference CC to the SS-MRCC methods increases after inclusion of even partial triple excitations. Generally, the performance of the SS-MRCCSDT-1a+d approach is closer to the corresponding full configuration interaction (FCI) one than to the SS-MRCCSDT-1a specially in the degenerate geometries (as is evident from nonparallelism error). The deviation from FCI for the first excited state of the P4 model using various SS-MRCC theories with different truncation schemes obtained by converging on the second root of the effective Hamiltonian has also been reported. We also compare our results with the current generation state-of-the-art single and multireference CC calculations to envisage the usefulness of the present approach. Initial implementation indicates that the SS-MRCCSDT-n formalism can provide not only reliable excitation energies and barrier height even when used in a relatively small model space, but also offers a considerable promise in generating the entire energy surface with low nonparallelity error.
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Affiliation(s)
- Uttam Sinha Mahapatra
- Department of Physics, Maulana Azad College, 8 Rafi Ahmed KidwaiRoad, Kolkata 700013, India.
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Hanauer M, Köhn A. Perturbative treatment of triple excitations in internally contracted multireference coupled cluster theory. J Chem Phys 2012; 136:204107. [DOI: 10.1063/1.4718700] [Citation(s) in RCA: 74] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Das S, Pathak S, Datta D, Mukherjee D. Inactive excitations in Mukherjee's state-specific multireference coupled cluster theory treated with internal contraction: Development and applications. J Chem Phys 2012; 136:164104. [DOI: 10.1063/1.3703312] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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22
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State-specific complete active space multireference Møller–Plesset perturbation approach for multireference situations: illustrating the bond breaking in hydrogen halides. Theor Chem Acc 2012. [DOI: 10.1007/s00214-012-1213-z] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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23
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Haunschild R, Mao S, Mukherjee D, Klopper W. A universal explicit electron correlation correction applied to Mukherjee’s multi-reference perturbation theory. Chem Phys Lett 2012. [DOI: 10.1016/j.cplett.2012.02.020] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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