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Damour Y, Scemama A, Jacquemin D, Kossoski F, Loos PF. State-Specific Coupled-Cluster Methods for Excited States. J Chem Theory Comput 2024; 20:4129-4145. [PMID: 38749498 PMCID: PMC11137840 DOI: 10.1021/acs.jctc.4c00034] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2024] [Revised: 03/06/2024] [Accepted: 03/06/2024] [Indexed: 05/29/2024]
Abstract
We reexamine ΔCCSD, a state-specific coupled-cluster (CC) with single and double excitations (CCSD) approach that targets excited states through the utilization of non-Aufbau determinants. This methodology is particularly efficient when dealing with doubly excited states, a domain in which the standard equation-of-motion CCSD (EOM-CCSD) formalism falls short. Our goal here to evaluate the effectiveness of ΔCCSD when applied to other types of excited states, comparing its consistency and accuracy with EOM-CCSD. To this end, we report a benchmark on excitation energies computed with the ΔCCSD and EOM-CCSD methods for a set of molecular excited-state energies that encompasses not only doubly excited states but also doublet-doublet transitions and (singlet and triplet) singly excited states of closed-shell systems. In the latter case, we rely on a minimalist version of multireference CC known as the two-determinant CCSD method to compute the excited states. Our data set, consisting of 276 excited states stemming from the quest database [Véril et al., WIREs Comput. Mol. Sci. 2021, 11, e1517], provides a significant base to draw general conclusions concerning the accuracy of ΔCCSD. Except for the doubly excited states, we found that ΔCCSD underperforms EOM-CCSD. For doublet-doublet transitions, the difference between the mean absolute errors (MAEs) of the two methodologies (of 0.10 and 0.07 eV) is less pronounced than that obtained for singly excited states of closed-shell systems (MAEs of 0.15 and 0.08 eV). This discrepancy is largely attributed to a greater number of excited states in the latter set exhibiting multiconfigurational characters, which are more challenging for ΔCCSD. We also found typically small improvements by employing state-specific optimized orbitals.
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Affiliation(s)
- Yann Damour
- Laboratoire
de Chimie et Physique Quantiques (UMR 5626), Université de Toulouse, CNRS, UPS, 31000 Toulouse, France
| | - Anthony Scemama
- Laboratoire
de Chimie et Physique Quantiques (UMR 5626), Université de Toulouse, CNRS, UPS, 31000 Toulouse, France
| | - Denis Jacquemin
- Nantes
Université, CNRS, CEISAM UMR 6230, F-44000 Nantes, France
- Institut
Universitaire de France (IUF), F-75005 Paris, France
| | - Fábris Kossoski
- Laboratoire
de Chimie et Physique Quantiques (UMR 5626), Université de Toulouse, CNRS, UPS, 31000 Toulouse, France
| | - Pierre-François Loos
- Laboratoire
de Chimie et Physique Quantiques (UMR 5626), Université de Toulouse, CNRS, UPS, 31000 Toulouse, France
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Schraivogel T, Kats D. Two determinant distinguishable cluster. J Chem Phys 2024; 160:124109. [PMID: 38526108 DOI: 10.1063/5.0199274] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2024] [Accepted: 03/06/2024] [Indexed: 03/26/2024] Open
Abstract
A two reference determinant version of the distinguishable cluster with singles and doubles (DCSD) has been developed. We have implemented the two determinant distinguishable cluster (2D-DCSD) and the corresponding traditional 2D-CCSD method in a new open-source package written in Julia called ElemCo.jl. The methods were benchmarked on singlet and triplet excited states of valence and Rydberg character, as well as for singlet-triplet gaps of diradicals. It is demonstrated that the distinguishable cluster approximation improves the accuracy of 2D-CCSD.
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Affiliation(s)
- Thomas Schraivogel
- Max Planck Institute for Solid State Research, Heisenbergstraße 1, 70569 Stuttgart, Germany
| | - Daniel Kats
- Max Planck Institute for Solid State Research, Heisenbergstraße 1, 70569 Stuttgart, Germany
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Lischka H, Nachtigallová D, Aquino AJA, Szalay PG, Plasser F, Machado FBC, Barbatti M. Multireference Approaches for Excited States of Molecules. Chem Rev 2018; 118:7293-7361. [DOI: 10.1021/acs.chemrev.8b00244] [Citation(s) in RCA: 197] [Impact Index Per Article: 32.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Affiliation(s)
- Hans Lischka
- School of Pharmaceutical Sciences and Technology, Tianjin University, Tianjin 300072, P.R. China
- Department of Chemistry and Biochemistry, Texas Tech University, Lubbock, Texas 79409, United States
- Institute of Theoretical Chemistry, Faculty of Chemistry, University of Vienna, Währinger Straße 17, 1090 Vienna, Austria
| | - Dana Nachtigallová
- Institute of Organic Chemistry and Biochemistry v.v.i., The Czech Academy of Sciences, Flemingovo nám. 2, 16610 Prague 6, Czech Republic
- Regional Centre of Advanced Technologies and Materials, Palacký University, 78371 Olomouc, Czech Republic
| | - Adélia J. A. Aquino
- School of Pharmaceutical Sciences and Technology, Tianjin University, Tianjin 300072, P.R. China
- Department of Chemistry and Biochemistry, Texas Tech University, Lubbock, Texas 79409, United States
- Institute for Soil Research, University of Natural Resources and Life Sciences Vienna, Peter-Jordan-Strasse 82, A-1190 Vienna, Austria
| | - Péter G. Szalay
- ELTE Eötvös Loránd University, Laboratory of Theoretical Chemistry, Pázmány Péter sétány 1/A, 1117 Budapest, Hungary
| | - Felix Plasser
- Institute of Theoretical Chemistry, Faculty of Chemistry, University of Vienna, Währinger Straße 17, 1090 Vienna, Austria
- Department of Chemistry, Loughborough University, Leicestershire LE11 3TU, United Kingdom
| | - Francisco B. C. Machado
- Departamento de Química, Instituto Tecnológico de Aeronáutica, São José dos Campos 12228-900, São Paulo, Brazil
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Lutz JJ, Nooijen M, Perera A, Bartlett RJ. Reference dependence of the two-determinant coupled-cluster method for triplet and open-shell singlet states of biradical molecules. J Chem Phys 2018; 148:164102. [DOI: 10.1063/1.5025170] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023] Open
Affiliation(s)
- Jesse J. Lutz
- Air Force Institute of Technology, Wright-Patterson Air Force Base, Ohio 45433, USA
- Quantum Theory Project, University of Florida, Gainesville, Florida 32611, USA
| | - Marcel Nooijen
- Department of Chemistry, University of Waterloo, Waterloo, Ontario N2L 3G1, Canada
| | - Ajith Perera
- Quantum Theory Project, University of Florida, Gainesville, Florida 32611, USA
| | - Rodney J. Bartlett
- Quantum Theory Project, University of Florida, Gainesville, Florida 32611, USA
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5
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Grochala W. The generalized maximum hardness principle revisited and applied to atoms and molecules. Phys Chem Chem Phys 2017; 19:30964-30983. [PMID: 28816324 DOI: 10.1039/c7cp03101g] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Part 1 of this duology is devoted to isolated atoms and molecules, and to chemical reactions between them; we introduce here basic concepts beyond the Generalized Maximum Hardness Principle, and the corresponding Minimum Polarizability Principle, and we illustrate applicability of both principles to a broad range of chemical phenomena and distinct systems in the gas phase.
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Affiliation(s)
- Wojciech Grochala
- Centre for New Technologies
- The University of Warsaw
- 02089 Warsaw
- Poland
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6
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Lewars E. The chemistry of bowtiene (tricyclo[5.3.0.0 2,6]decapentaene): a computational study. CAN J CHEM 2014. [DOI: 10.1139/cjc-2014-0004] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Reactions of bowtiene (tricyclo[5.3.0.02,6]decapentaene, cyclobuta[1,2:3,4]dicyclopentene, bicyclopentadienylene, a tricyclic analogue of [10]annulene), in the sphere of unimolecular decomposition and dimerization were studied computationally to gauge its stability and reactivity, which are relevant to its feasability as a synthetic goal. The intuitively likeliest rearrangement mode to give species of lower energy begins with rearrangement to the 1,5-dehydronaphthalene diradical; this was calculated to have a barrier of approximately 220 kJ mol−1, too high for reaction at room temperature. Nevertheless, the energetics of rearrangement of the 1,5-diradical to the monocyclic 1,6-didehydro[10]annulene, a species of interest regarding its relationship to bowtiene and the diradical, were studied. The energy of bowtiene was compared with that of several other tricyclic 10π C10H6cyclic polyenes.
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Affiliation(s)
- Errol Lewars
- Department of Chemistry, Trent University, Peterborough, ON K9J 7B8, Canada
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7
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Bartlett RJ. Coupled‐cluster theory and its equation‐of‐motion extensions. WILEY INTERDISCIPLINARY REVIEWS-COMPUTATIONAL MOLECULAR SCIENCE 2011. [DOI: 10.1002/wcms.76] [Citation(s) in RCA: 226] [Impact Index Per Article: 17.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
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8
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Musiał M, Perera A, Bartlett RJ. Multireference coupled-cluster theory: The easy way. J Chem Phys 2011; 134:114108. [DOI: 10.1063/1.3567115] [Citation(s) in RCA: 102] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
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Garbuio V, Cascella M, Pulci O. Excited state properties of liquid water. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2009; 21:033101. [PMID: 21817245 DOI: 10.1088/0953-8984/21/3/033101] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
In this paper, we give an overview of the state of the art in calculations of the electronic band structure and absorption spectra of water. After an introduction to the main theoretical and computational schemes used, we present results for the electronic and optical excitations of water. We focus mainly on liquid water, but spectroscopic properties of ice and vapor phase are also described. The applicability and the accuracy of first-principles methods are discussed, and results are critically presented.
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Affiliation(s)
- Viviana Garbuio
- European Theoretical Spectroscopy Facility (ETSF), CNR-INFM-SMC, Department of Physics University of Rome Tor Vergata, Italy
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11
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Páleníková J, Kraus M, Neogrády P, Kellö V, Urban M. Theoretical study of molecular properties of low-lying electronic excited states of H2O and H2S. Mol Phys 2008. [DOI: 10.1080/00268970802454786] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Affiliation(s)
- Jana Páleníková
- a Faculty of Natural Sciences, Department of Physical and Theoretical Chemistry , Comenius University , Bratislava, Slovakia
| | - Michal Kraus
- a Faculty of Natural Sciences, Department of Physical and Theoretical Chemistry , Comenius University , Bratislava, Slovakia
| | - Pavel Neogrády
- a Faculty of Natural Sciences, Department of Physical and Theoretical Chemistry , Comenius University , Bratislava, Slovakia
| | - Vladimir Kellö
- a Faculty of Natural Sciences, Department of Physical and Theoretical Chemistry , Comenius University , Bratislava, Slovakia
| | - Miroslav Urban
- a Faculty of Natural Sciences, Department of Physical and Theoretical Chemistry , Comenius University , Bratislava, Slovakia
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12
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Crawford TD, Schaefer HF. An Introduction to Coupled Cluster Theory for Computational Chemists. REVIEWS IN COMPUTATIONAL CHEMISTRY 2007. [DOI: 10.1002/9780470125915.ch2] [Citation(s) in RCA: 372] [Impact Index Per Article: 21.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/05/2022]
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13
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Nigam S, Majumder C, Kulshreshtha SK. Structural and electronic properties of Sin, Sin−, and PSin−1 clusters (2⩽n⩽13): Theoretical investigation based on ab initio molecular orbital theory. J Chem Phys 2006; 125:074303. [PMID: 16942335 DOI: 10.1063/1.2244569] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
The geometric and electronic structures of Si(n), Si(n)-, and PSi(n-1) clusters (2 < or = n < or = 13) have been investigated using the ab initio molecular orbital theory formalism. The hybrid exchange-correlation energy functional (B3LYP) and a standard split-valence basis set with polarization functions (6-31+G(d)) were employed to optimize geometrical configurations. The total energies of the lowest energy isomers thus obtained were recalculated at the MP2/aug-cc-pVTZ level of theory. Unlike positively charged clusters, which showed similar structural behavior as that of neutral clusters [Nigam et al., J. Chem. Phys. 121, 7756 (2004)], significant geometrical changes were observed between Si(n) and Si(n)- clusters for n = 6, 8, 11, and 13. However, the geometries of P substituted silicon clusters show similar growth as that of negatively charged Si(n) clusters with small local distortions. The relative stability as a function of cluster size has been verified based on their binding energies, second difference in energy (Delta2 E), and fragmentation behavior. In general, the average binding energy of Si(n)- clusters is found to be higher than that of Si(n) clusters. For isoelectronic PSi(n-1) clusters, it is found that although for small clusters (n < 4) substitution of P atom improves the binding energy of Si(n) clusters, for larger clusters (n > or = 4) the effect is opposite. The fragmentation behavior of these clusters reveals that while small clusters prefer to evaporate monomer, the larger ones dissociate into two stable clusters of smaller size. The adiabatic electron affinities of Si(n) clusters and vertical detachment energies of Si(n)- clusters were calculated and compared with available experimental results. Finally, a good agreement between experimental and our theoretical results suggests good prediction of the lowest energy isomeric structures for all clusters calculated in the present study.
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Affiliation(s)
- Sandeep Nigam
- Chemistry Division, Bhabha Atomic Research Center, Trombay, Mumbai 400 085, India
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14
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Ivanov VV, Adamowicz L, Lyakh DI. Potential energy surface of the electron excited states in the state-specific multi-reference coupled cluster theory. Hydrogen fluoride dissociation. ACTA ACUST UNITED AC 2006. [DOI: 10.1016/j.theochem.2006.04.043] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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15
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Ivanov VV, Adamowicz L, Lyakh DI. Excited states in the multireference state-specific coupled-cluster theory with the complete active space reference. J Chem Phys 2006; 124:184302. [PMID: 16709101 DOI: 10.1063/1.2190221] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
The recently proposed multireference state-specific coupled-cluster theory with the complete active space reference has been used to study electronically excited states with different spatial and spin symmetries. The algorithm for the method has been obtained using the computerized approach for automatic generation of coupled-cluster diagrams with an arbitrary level of the electronic excitation from a formal reference determinant. The formal reference is also used to generate the genuine reference state in the form of a linear combination of determinants contracted to a configuration with the spin and spatial symmetries of the target state. The natural-orbital expansions of the one-electron configuration inferaction density matrix allowed us to obtain the most compact orbital space for the expansion of the reference function. We applied our approach in the calculations of singlet and triplet states of different spatial symmetries of the water molecule. The comparisons of the results with values obtained using other many-particle methods and with the full configuration interaction results demonstrate good ability of the approach to deal with electronic excited states.
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Affiliation(s)
- Vladimir V Ivanov
- Department of Chemistry, V.N. Karazin Kharkov National University, Kharkov, Ukraine
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16
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Muchová E, Spirko V, Hobza P, Nachtigallová D. Theoretical study of photoacidity of HCN: the effect of complexation with water. Phys Chem Chem Phys 2006; 8:4866-73. [PMID: 17066176 DOI: 10.1039/b610001e] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The character of the hydrogen bonding and the excited state proton transfer (ESPT) in the model system HCN...H(2)O is investigated. The PES of the two lowest excited states of the H(2)O...HCN complex was calculated using the CASPT2 method. The nonadiabatic coupling of the two states of the (pi-->pi*) and (pi-->sigma*) character is responsible for the excited state proton/hydrogen transfer. Compared to the ground state, the barrier for this process is significantly smaller. An increased number of water molecules in the complex with cyclic hydrogen-bonded network causes a large blue shift of the state of the (pi-->sigma*) character. The question of the dissociation of the complex in its excited state is also addressed.
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Affiliation(s)
- Eva Muchová
- Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic and Center for Biomolecules and Complex Molecular Systems, Flemingovo nam. 2, 166 10, Prague 6
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17
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Miller Y, Fredj E, Harvey JN, Gerber RB. Ultraviolet Spectroscopy of Large Water Clusters: Model and Calculations for (H2O)n, for n = 8, 11, 20, 40, and 50. J Phys Chem A 2004. [DOI: 10.1021/jp030678b] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Affiliation(s)
- Y. Miller
- Department of Physical Chemistry and The Fritz Haber Research Center, The Hebrew University, Jerusalem 91904, Israel, Computer Science Department, Jerusalem College of TechnologyMachon Lev, Jerusalem 91160, Israel, School of Chemistry, University of Bristol, Bristol BS8 1TS, England, and Department of Chemistry, University of California, Irvine, California 92697-2025
| | - E. Fredj
- Department of Physical Chemistry and The Fritz Haber Research Center, The Hebrew University, Jerusalem 91904, Israel, Computer Science Department, Jerusalem College of TechnologyMachon Lev, Jerusalem 91160, Israel, School of Chemistry, University of Bristol, Bristol BS8 1TS, England, and Department of Chemistry, University of California, Irvine, California 92697-2025
| | - J. N. Harvey
- Department of Physical Chemistry and The Fritz Haber Research Center, The Hebrew University, Jerusalem 91904, Israel, Computer Science Department, Jerusalem College of TechnologyMachon Lev, Jerusalem 91160, Israel, School of Chemistry, University of Bristol, Bristol BS8 1TS, England, and Department of Chemistry, University of California, Irvine, California 92697-2025
| | - R. B. Gerber
- Department of Physical Chemistry and The Fritz Haber Research Center, The Hebrew University, Jerusalem 91904, Israel, Computer Science Department, Jerusalem College of TechnologyMachon Lev, Jerusalem 91160, Israel, School of Chemistry, University of Bristol, Bristol BS8 1TS, England, and Department of Chemistry, University of California, Irvine, California 92697-2025
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18
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Cai ZL, Tozer DJ, Reimers JR. Time-dependent density-functional determination of arbitrary singlet and triplet excited-state potential energy surfaces: Application to the water molecule. J Chem Phys 2000. [DOI: 10.1063/1.1312826] [Citation(s) in RCA: 58] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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19
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Cai ZL, Reimers JR. Application of time-dependent density-functional theory to the 3Σu− first excited state of H2. J Chem Phys 2000. [DOI: 10.1063/1.480544] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.0] [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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Piecuch P, Bartlett RJ. EOMXCC: A New Coupled-Cluster Method for Electronic Excited States. ADVANCES IN QUANTUM CHEMISTRY 1999. [DOI: 10.1016/s0065-3276(08)60534-1] [Citation(s) in RCA: 98] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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21
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Harvey JN, Jung JO, Gerber RB. Ultraviolet spectroscopy of water clusters: Excited electronic states and absorption line shapes of (H2O)n, n=2–6. J Chem Phys 1998. [DOI: 10.1063/1.477542] [Citation(s) in RCA: 51] [Impact Index Per Article: 2.0] [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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Andrejkovics I, Nagy Á. Excitation energies in density functional theory: comparison of several methods for the H2O, N2, CO and C2H4 molecules. Chem Phys Lett 1998. [DOI: 10.1016/s0009-2614(98)01075-6] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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23
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Multireference Brillouin-Wigner Coupled-Cluster Theory. Single-root approach. ADVANCES IN QUANTUM CHEMISTRY 1998. [DOI: 10.1016/s0065-3276(08)60184-7] [Citation(s) in RCA: 141] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
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Schatz GC, Papaioannou A, Pederson LA, Harding LB, Hollebeek T, Ho TS, Rabitz H. A global A-state potential surface for H2O: Influence of excited states on the O(1D)+H2 reaction. J Chem Phys 1997. [DOI: 10.1063/1.474614] [Citation(s) in RCA: 115] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
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Klein S, Kochanski E, Strich A. Electric properties of the oxonium ion in its ground and two lowest excited states. Chem Phys Lett 1996. [DOI: 10.1016/0009-2614(96)00818-4] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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Electric properties of the water molecule in 1A1, 1B1, and 3B1 electronic states: Refined CASSCF and CASPT2 calculations. ACTA ACUST UNITED AC 1996. [DOI: 10.1007/bf00194933] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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Affiliation(s)
| | - James B. Anderson
- Department of Chemistry, The Pennsylvania State University, University Park, Pennsylvania 16802
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28
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Ghose KB, Piecuch P, Pal S, Adamowicz L. State‐selective multireference coupled‐cluster theory: In pursuit of property calculation. J Chem Phys 1996. [DOI: 10.1063/1.471378] [Citation(s) in RCA: 55] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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29
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Nooijen M, Bartlett RJ. General spin adaptation of open‐shell coupled cluster theory. J Chem Phys 1996. [DOI: 10.1063/1.471010] [Citation(s) in RCA: 51] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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30
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Ghose KB, Piecuch P, Adamowicz L. Improved computational strategy for the state‐selective coupled‐cluster theory with semi‐internal triexcited clusters: Potential energy surface of the HF molecule. J Chem Phys 1995. [DOI: 10.1063/1.469993] [Citation(s) in RCA: 94] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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31
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Warken M. Perturbation theory for electronic excited states: The low lying Rydberg states of water. J Chem Phys 1995. [DOI: 10.1063/1.470725] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
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32
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Nooijen M, Bartlett RJ. Description of core‐excitation spectra by the open‐shell electron‐attachment equation‐of‐motion coupled cluster method. J Chem Phys 1995. [DOI: 10.1063/1.469147] [Citation(s) in RCA: 146] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Nooijen M, Bartlett RJ. Equation of motion coupled cluster method for electron attachment. J Chem Phys 1995. [DOI: 10.1063/1.468592] [Citation(s) in RCA: 453] [Impact Index Per Article: 15.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Piecuch P, Paldus J. Orthogonally spin‐adapted state‐universal coupled‐cluster formalism: Implementation of the complete two‐reference theory including cubic and quartic coupling terms. J Chem Phys 1994. [DOI: 10.1063/1.467304] [Citation(s) in RCA: 105] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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35
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Szalay PG, Bartlett RJ. Analytic energy gradients for the two‐determinant coupled cluster method with application to singlet excited states of butadiene and ozone. J Chem Phys 1994. [DOI: 10.1063/1.467416] [Citation(s) in RCA: 54] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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