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Marie A, Loos PF. Reference Energies for Valence Ionizations and Satellite Transitions. J Chem Theory Comput 2024; 20:4751-4777. [PMID: 38776293 PMCID: PMC11171335 DOI: 10.1021/acs.jctc.4c00216] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2024] [Revised: 04/10/2024] [Accepted: 04/11/2024] [Indexed: 05/24/2024]
Abstract
Upon ionization of an atom or a molecule, another electron (or more) can be simultaneously excited. These concurrently generated states are called "satellites" (or shakeup transitions) as they appear in ionization spectra as higher-energy peaks with weaker intensity and larger width than the main peaks associated with single-particle ionizations. Satellites, which correspond to electronically excited states of the cationic species, are notoriously challenging to model using conventional single-reference methods due to their high excitation degree compared to the neutral reference state. This work reports 42 satellite transition energies and 58 valence ionization potentials (IPs) of full configuration interaction quality computed in small molecular systems. Following the protocol developed for the quest database [Véril, M.; Scemama, A.; Caffarel, M.; Lipparini, F.; Boggio-Pasqua, M.; Jacquemin, D.; and Loos, P.-F. Wiley Interdiscip. Rev.: Comput. Mol. Sci. 2021, 11, e1517], these reference energies are computed using the configuration interaction using a perturbative selection made iteratively (CIPSI) method. In addition, the accuracy of the well-known coupled-cluster (CC) hierarchy (CC2, CCSD, CC3, CCSDT, CC4, and CCSDTQ) is gauged against these new accurate references. The performances of various approximations based on many-body Green's functions (GW, GF2, and T-matrix) for IPs are also analyzed. Their limitations in correctly modeling satellite transitions are discussed.
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Affiliation(s)
- Antoine Marie
- Laboratoire de Chimie et Physique
Quantiques (UMR 5626), Université de Toulouse, CNRS, UPS, Toulouse 31062, France
| | - Pierre-François Loos
- Laboratoire de Chimie et Physique
Quantiques (UMR 5626), Université de Toulouse, CNRS, UPS, Toulouse 31062, France
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2
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Pant R, Ranga S, Bachhar A, Dutta AK. Pair Natural Orbital Equation-of-Motion Coupled-Cluster Method for Core Binding Energies: Theory, Implementation, and Benchmark. J Chem Theory Comput 2022; 18:4660-4673. [PMID: 35786933 DOI: 10.1021/acs.jctc.2c00165] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
We present the theory and implementation of a lower scaling core-valence separated equation-of-motion coupled-cluster approach based on domain-based local pair natural orbitals for core binding energies. The accuracy of the new method has been compared with that of the standard equation-of-motion coupled-cluster method and experimentally measured results. The use of pair natural orbitals significantly reduces the computation cost and can be applied to large molecules.
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Affiliation(s)
- Rakesh Pant
- Department of Chemistry, Indian Institute of Technology Bombay, Powai, Mumbai 400076, India
| | - Santosh Ranga
- Department of Chemistry, Indian Institute of Technology Bombay, Powai, Mumbai 400076, India
| | - Arnab Bachhar
- Department of Chemistry, Indian Institute of Technology Bombay, Powai, Mumbai 400076, India
| | - Achintya Kumar Dutta
- Department of Chemistry, Indian Institute of Technology Bombay, Powai, Mumbai 400076, India
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3
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Ranga S, Dutta AK. A Core-Valence Separated Similarity Transformed EOM-CCSD Method for Core-Excitation Spectra. J Chem Theory Comput 2021; 17:7428-7446. [PMID: 34814683 DOI: 10.1021/acs.jctc.1c00402] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
We present the theory and implementation of a core-valence separated similarity transformed EOM-CCSD (STEOM-CCSD) method for K-edge core excitation spectra. The method can select an appropriate active space using CIS natural orbitals and near "black box" to use. The second similarity transformed Hamiltonian is diagonalized in the space of single excitation. Therefore, the final diagonalization step is free from the convergence problem arising due to the coupling of the core-excited states with the continuum of doubly excited states. Convergence trouble can appear for the preceding core-ionized state calculation in STEOM-CCSD. A core-valence separation (CVS) scheme compatible with the natural orbital based active space selection (CVS-STEOM-CCSD-NO) is implemented to overcome the problem. The CVS-STEOM-CCSD-NO has a similar accuracy to that of the standard CVS-EOM-CCSD method but comes with a lower computational cost. The modification required in the CVS scheme to make use of the CIS natural orbital is highlighted. The suitability of the CVS-STEOM-CCSD-NO method for chemical application is demonstrated by simulating the K-edge spectra of glycine and thymine.
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Affiliation(s)
- Santosh Ranga
- Department of Chemistry, Indian Institute of Technology Bombay, Powai, Mumbai 400076, India
| | - Achintya Kumar Dutta
- Department of Chemistry, Indian Institute of Technology Bombay, Powai, Mumbai 400076, India
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4
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Su NQ, Xu X. Perturbation theory made efficient and effective for predictions of ionization potential and electron affinity. J Chem Phys 2021; 154:174101. [PMID: 34241082 DOI: 10.1063/5.0047956] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Ionization potential and electron affinity are essential molecular properties. The most straightforward method is to calculate them by taking the total energy differences of the initial and final states according to the definition. However, it often suffers from a serious convergence problem due to the requirement of the self-consistent field (SCF) calculations for the ionic states with non-Aufbau choices of occupations. In the present work, we have constructed a theoretical framework in view of perturbation theory to bypass the SCF calculations of the ionic states. To address the imbalance issue that arises from the precisely treated neutral ground state followed by the truncated perturbative treatment of the ionic states, an accurate yet effective method has been developed here, which adds back some terms from the higher order perturbations into the lower order to cancel out the most computationally cost terms in the truncated expansion, thus reaching a better convergence with less computation. The validity of the present methodology has been tested out by applying it to the Hartree-Fock (HF) method in combination with the correlation effect described at the second-order Møller-Plesset level in a frozen-orbital approximation. All the derivations in this work are given in a general framework, which are applicable not only to HF but also to a wide range of density functional theory methods from semi-local functionals to hybrid and doubly hybrid functionals.
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Affiliation(s)
- Neil Qiang Su
- Collaborative Innovation Center of Chemistry for Energy Materials, Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials, Ministry of Education Key Laboratory of Computational Physical Sciences, Department of Chemistry, Fudan University, Shanghai 200433, China
| | - Xin Xu
- Collaborative Innovation Center of Chemistry for Energy Materials, Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials, Ministry of Education Key Laboratory of Computational Physical Sciences, Department of Chemistry, Fudan University, Shanghai 200433, China
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5
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Mukherjee M, Tripathi D, Brehm M, Riplinger C, Dutta AK. Efficient EOM-CC-based Protocol for the Calculation of Electron Affinity of Solvated Nucleobases: Uracil as a Case Study. J Chem Theory Comput 2020; 17:105-116. [DOI: 10.1021/acs.jctc.0c00655] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Affiliation(s)
| | - Divya Tripathi
- Indian Institute of Technology Bombay, Powai, Mumbai 400076, India
| | - Martin Brehm
- Institute of Chemistry, Martin Luther University Halle-Wittenberg, Von-Danckelmann-Platz 4, 06120 Halle (Saale), Germany
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6
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de Souza GLC, Peterson KA. Probing the ionization potentials of the formaldehyde dimer. J Chem Phys 2020; 152:194305. [PMID: 33687222 DOI: 10.1063/5.0009658] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
In this work, we present a computational investigation on the ionization potentials (IPs) of the formaldehyde dimer, (H2CO)2. Twelve lowest lying IPs (corresponding to the entire valence orbitals) for both C2h and Cs symmetry conformers have been computed at the coupled cluster level of theory using large correlation consistent basis sets with extrapolation to the complete basis set limit and consideration of core electron correlation effects. Specifically, the equation-of-motion ionization potential coupled-cluster with single and double (EOMIP-CCSD) excitations method with the aug-cc-pVXZ and aug-cc-pCVXZ (X = T, Q, and 5) basis sets combined with the Feller-Peterson-Dixon approach was employed, as well as CCSD with perturbative triples [CCSD(T)] with the aug-cc-pVTZ basis sets. In general, excellent agreement was observed from the comparison between the results obtained through the use of these approaches. In addition, the IPs for the formaldehyde monomer were also obtained using such methodologies and the results compared with existing experimental data; excellent agreement was also observed in this case. To the best of our knowledge, this work represents the first of its kind to determine the IPs for all these systems using a high level theory approach and is presented to motivate experimental investigations, e.g., studies involving photoionization, particularly for the formaldehyde dimer. The equilibrium binding energy of the C2h dimer is calculated in this work at the CCSD(T)/aug-cc-pVTZ level of theory to be -4.71 kcal/mol. At this same level of theory, the equilibrium isomerization energy between C2h and Cs conformers is 0.76 kcal/mol (Cs conformer being more stable).
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Affiliation(s)
- Gabriel L C de Souza
- Departamento de Química, Universidade Federal de Mato Grosso, Cuiabá, Mato Grosso 78060-900, Brazil
| | - Kirk A Peterson
- Department of Chemistry, Washington State University, Pullman, Washington 99164, USA
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7
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Haldar S, Dutta AK. A Multilayer Approach to the Equation of Motion Coupled-Cluster Method for the Electron Affinity. J Phys Chem A 2020; 124:3947-3962. [DOI: 10.1021/acs.jpca.0c01793] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Affiliation(s)
- Soumi Haldar
- Department of Chemistry, Indian Institute of Technology Bombay, Powai, Mumbai 400076, India
| | - Achintya Kumar Dutta
- Department of Chemistry, Indian Institute of Technology Bombay, Powai, Mumbai 400076, India
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8
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Gu Y, Xu X. A correlation–relaxation-balanced direct method at the second order perturbation theory for accurate ionization potential predictions. Phys Chem Chem Phys 2020; 22:22342-22348. [DOI: 10.1039/d0cp03430d] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
With almost no extra computational cost after a normal MP2 procedure, the CRB-MP2 method proposed here yields high quality valence and core IPs for a wide range of species.
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Affiliation(s)
- Yonghao Gu
- Collaborative Innovation Center of Chemistry for Energy Materials
- Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials
- Ministry of Education Key Laboratory of Computational Physical Sciences
- Department of Chemistry
- Fudan University
| | - Xin Xu
- Collaborative Innovation Center of Chemistry for Energy Materials
- Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials
- Ministry of Education Key Laboratory of Computational Physical Sciences
- Department of Chemistry
- Fudan University
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9
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Izsák R. Single‐reference coupled cluster methods for computing excitation energies in large molecules: The efficiency and accuracy of approximations. WILEY INTERDISCIPLINARY REVIEWS-COMPUTATIONAL MOLECULAR SCIENCE 2019. [DOI: 10.1002/wcms.1445] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Affiliation(s)
- Róbert Izsák
- Max‐Planck‐Institut für Kohlenforschung Mülheim an der Ruhr Germany
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10
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Dutta AK, Saitow M, Demoulin B, Neese F, Izsák R. A domain-based local pair natural orbital implementation of the equation of motion coupled cluster method for electron attached states. J Chem Phys 2019; 150:164123. [DOI: 10.1063/1.5089637] [Citation(s) in RCA: 45] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Affiliation(s)
| | - Masaaki Saitow
- Department of Chemistry, Graduate School of Science, Nagoya University, 1-5 Chikusa-ku, Nagoya, Aichi 464-8602, Japan
| | - Baptiste Demoulin
- Max-Planck-Institut für Kohlenforschung, Kaiser-Wilhelm Platz 1, 45470 Mülheim an der Ruhr, Germany
| | - Frank Neese
- Max-Planck-Institut für Kohlenforschung, Kaiser-Wilhelm Platz 1, 45470 Mülheim an der Ruhr, Germany
| | - Róbert Izsák
- Max-Planck-Institut für Kohlenforschung, Kaiser-Wilhelm Platz 1, 45470 Mülheim an der Ruhr, Germany
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11
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Sen A, de Souza B, Huntington LMJ, Krupička M, Neese F, Izsák R. An efficient pair natural orbital based configuration interaction scheme for the calculation of open-shell ionization potentials. J Chem Phys 2018; 149:114108. [DOI: 10.1063/1.5048688] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- Avijit Sen
- Max-Planck-Institut für Kohlenforschung, Kaiser-Wilhelm-Platz 1, D-45470 Mülheim an der Ruhr, Germany
| | - Bernardo de Souza
- Max-Planck-Institute for Chemical Energy Conversion, Mülheim an der Ruhr, Germany
- Universidade Federal de Santa Catarina, Florianópolis, Brazil
| | - Lee M. J. Huntington
- Max-Planck-Institute for Chemical Energy Conversion, Mülheim an der Ruhr, Germany
| | - Martin Krupička
- Max-Planck-Institute for Chemical Energy Conversion, Mülheim an der Ruhr, Germany
- University of Chemistry and Technology, Prague, Czech Republic
| | - Frank Neese
- Max-Planck-Institut für Kohlenforschung, Kaiser-Wilhelm-Platz 1, D-45470 Mülheim an der Ruhr, Germany
| | - Róbert Izsák
- Max-Planck-Institut für Kohlenforschung, Kaiser-Wilhelm-Platz 1, D-45470 Mülheim an der Ruhr, Germany
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12
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Dutta AK, Saitow M, Riplinger C, Neese F, Izsák R. A near-linear scaling equation of motion coupled cluster method for ionized states. J Chem Phys 2018; 148:244101. [DOI: 10.1063/1.5029470] [Citation(s) in RCA: 40] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Affiliation(s)
- Achintya Kumar Dutta
- Max-Planck-Institut für Chemische Energiekonversion, Stiftstr. 34-36, D-45470 Mülheim an der Ruhr, Germany
| | - Masaaki Saitow
- Max-Planck-Institut für Chemische Energiekonversion, Stiftstr. 34-36, D-45470 Mülheim an der Ruhr, Germany
| | | | - Frank Neese
- Max-Planck-Institut für Kohlenforschung, Kaiser-Wilhelm Platz 1, 45470 Mülheim an der Ruhr, Germany
| | - Róbert Izsák
- Max-Planck-Institut für Kohlenforschung, Kaiser-Wilhelm Platz 1, 45470 Mülheim an der Ruhr, Germany
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13
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Dutta AK, Nooijen M, Neese F, Izsák R. Exploring the Accuracy of a Low Scaling Similarity Transformed Equation of Motion Method for Vertical Excitation Energies. J Chem Theory Comput 2017; 14:72-91. [DOI: 10.1021/acs.jctc.7b00802] [Citation(s) in RCA: 72] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Achintya Kumar Dutta
- Max-Planck-Institut für Chemische Energiekonversion, Stiftstr. 34-36, 45470 Mülheim an der Ruhr, Germany
| | - Marcel Nooijen
- Department of Chemistry, University of Waterloo, Waterloo, Ontario N2L 3G1, Canada
| | - Frank Neese
- Max-Planck-Institut für Chemische Energiekonversion, Stiftstr. 34-36, 45470 Mülheim an der Ruhr, Germany
| | - Róbert Izsák
- Max-Planck-Institut für Chemische Energiekonversion, Stiftstr. 34-36, 45470 Mülheim an der Ruhr, Germany
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14
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Kumar D, Dutta AK, Manohar PU. Resolution of the Identity and Cholesky Representation of EOM-MP2 Approximation: Implementation, Accuracy and Efficiency. J CHEM SCI 2017. [DOI: 10.1007/s12039-017-1378-z] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
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15
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Ronca E, Li Z, Jimenez-Hoyos CA, Chan GKL. Time-Step Targeting Time-Dependent and Dynamical Density Matrix Renormalization Group Algorithms with ab Initio Hamiltonians. J Chem Theory Comput 2017; 13:5560-5571. [DOI: 10.1021/acs.jctc.7b00682] [Citation(s) in RCA: 37] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Enrico Ronca
- Division of Chemistry and
Chemical Engineering, California Institute of Technology, Pasadena, California 91125, United States
| | - Zhendong Li
- Division of Chemistry and
Chemical Engineering, California Institute of Technology, Pasadena, California 91125, United States
| | - Carlos A. Jimenez-Hoyos
- Division of Chemistry and
Chemical Engineering, California Institute of Technology, Pasadena, California 91125, United States
| | - Garnet Kin-Lic Chan
- Division of Chemistry and
Chemical Engineering, California Institute of Technology, Pasadena, California 91125, United States
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16
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Dutta AK, Neese F, Izsák R. A simple scheme for calculating approximate transition moments within the equation of motion expectation value formalism. J Chem Phys 2017; 146:214111. [PMID: 28595413 PMCID: PMC5461178 DOI: 10.1063/1.4984618] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2017] [Accepted: 05/17/2017] [Indexed: 11/15/2022] Open
Abstract
A simple scheme for calculating approximate transition moments within the framework of the equation of motion coupled cluster method is proposed. It relies on a matrix inversion technique to calculate the excited state left eigenvectors and requires no additional cost over that of the excitation energy calculation. The new approximation gives almost identical UV-Vis spectra to that obtained using the standard equation of motion coupled cluster method with single and double excitations for molecules in a standard test set.
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Affiliation(s)
- Achintya Kumar Dutta
- Max-Planck-Institut für Chemische Energiekonversion, Stiftstr. 34-36, 45470 Mülheim an der Ruhr, Germany
| | - Frank Neese
- Max-Planck-Institut für Chemische Energiekonversion, Stiftstr. 34-36, 45470 Mülheim an der Ruhr, Germany
| | - Róbert Izsák
- Max-Planck-Institut für Chemische Energiekonversion, Stiftstr. 34-36, 45470 Mülheim an der Ruhr, Germany
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17
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Rishi V, Perera A, Nooijen M, Bartlett RJ. Excited states from modified coupled cluster methods: Are they any better than EOM CCSD? J Chem Phys 2017; 146:144104. [DOI: 10.1063/1.4979078] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Affiliation(s)
- Varun Rishi
- Quantum Theory Project, Department of Chemistry, University of Florida, Gainesville, Florida 32611, USA
| | - Ajith Perera
- Quantum Theory Project, Department of Chemistry, University of Florida, Gainesville, Florida 32611, USA
| | - Marcel Nooijen
- Department of Chemistry, University of Waterloo, Waterloo, Ontario N2L 3G1, Canada
| | - Rodney J. Bartlett
- Quantum Theory Project, Department of Chemistry, University of Florida, Gainesville, Florida 32611, USA
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18
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Cao Z, Wang F, Yang M. Spin-orbit coupling with approximate equation-of-motion coupled-cluster method for ionization potential and electron attachment. J Chem Phys 2016; 145:154110. [DOI: 10.1063/1.4964859] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Affiliation(s)
- Zhanli Cao
- Institute of Atomic and Molecular Physics, Key Laboratory of High Energy Density Physics and Technology, Ministry of Education, Sichuan University, Chengdu 610065, People’s Republic of China
| | - Fan Wang
- Institute of Atomic and Molecular Physics, Key Laboratory of High Energy Density Physics and Technology, Ministry of Education, Sichuan University, Chengdu 610065, People’s Republic of China
| | - Mingli Yang
- Institute of Atomic and Molecular Physics, Key Laboratory of High Energy Density Physics and Technology, Ministry of Education, Sichuan University, Chengdu 610065, People’s Republic of China
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19
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Dutta AK, Neese F, Izsák R. Towards a pair natural orbital coupled cluster method for excited states. J Chem Phys 2016; 145:034102. [DOI: 10.1063/1.4958734] [Citation(s) in RCA: 98] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023] Open
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20
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Das S, Sengupta T, Dutta AK, Pal S. Electron Detachment and Subsequent Structural Changes of Water Clusters. J Phys Chem A 2016; 120:1065-73. [PMID: 26835702 DOI: 10.1021/acs.jpca.5b09389] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
A cost-effective equation of motion coupled cluster method, EOMIP-CCSD(2), is used to investigate vertical and adiabatic ionization potential as well as ionization-induced structural changes of water clusters and compared with CCSD(T), CASPT2, and MP2 methods. The moderate N(5) scaling and low storage requirement yields EOMIP-CCSD(2) calculation feasible even for reasonably large molecules and clusters with accuracy comparable to CCSD(T) method at much cheaper computational cost. Our calculations shed light on the authenticity of EOMIP-CCSD(2) results and establish a reliable method to study of ionization energy of molecular clusters. We have further investigated the performance of several classes of DFT functionals for ionization energies of water clusters to benchmark the results and to get a reliable functionals for the same.
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Affiliation(s)
- Susanta Das
- Physical Chemistry Division, CSIR-National Chemical Laboratory , Pune 411008, India
| | - Turbasu Sengupta
- Physical Chemistry Division, CSIR-National Chemical Laboratory , Pune 411008, India
| | - Achintya Kumar Dutta
- Physical Chemistry Division, CSIR-National Chemical Laboratory , Pune 411008, India
| | - Sourav Pal
- Department of Chemistry, Indian institute of Technology Bombay , Powai, Mumbai 400 076, India
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21
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Dutta AK, Neese F, Izsák R. Speeding up equation of motion coupled cluster theory with the chain of spheres approximation. J Chem Phys 2016; 144:034102. [DOI: 10.1063/1.4939844] [Citation(s) in RCA: 55] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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