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Ludovicy J, Dahl R, Lüchow A. Toward Compact Selected Configuration Interaction Wave Functions with Quantum Monte Carlo─A Case Study of C 2. J Chem Theory Comput 2023; 19:2792-2803. [PMID: 37130194 DOI: 10.1021/acs.jctc.2c01229] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
The 1Σg+ ground state of C2 is investigated using truncated CIPSI-Jastrow CSF wave functions with Hartree-Fock orbitals within the framework of variational and diffusion quantum Monte Carlo. The truncation is performed based on the absolute value of the CI coefficients, and the Jastrow, molecular orbitals, and CI parameters are either partially or fully reoptimized with respect to the variational energy. Excellent absolute as well as bond dissociation energies are obtained at DMC level with very compact, fully optimized wave functions. By studying the expansions in more detail, we observe a change in the CI picture when reoptimizing the antisymmetric part of the CIPSI-Jastrow wave functions. Furthermore, we demonstrate that a decrease in the VMC energy as well as an improvement of the nodal surface quality can be achieved─with the same expansion size─if the CSFs are selected in the presence of a Jastrow correlation function, laying the foundation for a Jastrow selected CI scheme with quantum Monte Carlo.
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Affiliation(s)
- Jil Ludovicy
- Institute of Physical Chemistry, RWTH Aachen University, Landoltweg 2, 52074 Aachen, Germany
| | - Robin Dahl
- Institute of Physical Chemistry, RWTH Aachen University, Landoltweg 2, 52074 Aachen, Germany
| | - Arne Lüchow
- Institute of Physical Chemistry, RWTH Aachen University, Landoltweg 2, 52074 Aachen, Germany
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2
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Abstract
ConspectusDicarbon, the molecule formed from two carbon atoms, is among the most abundant molecules in the universe. Said by some to exhibit a quadruple bond, it is bound by more than 6 eV and supports a large number of valence electronic states. It thus has a rich spectroscopy, with 19 one-photon band systems, four of which were discovered by the author and co-workers. Its spectrum was among the first to be described: Wollaston reported the emission spectra from blue flames in 1802.C2 is observed in a variety of astronomical objects, including stars, circumstellar shells, nebulae, comets and the interstellar medium. It is responsible for the green color of cometary comae but is not observed in the comet tail. It can be observed in absorption and emission by optical spectroscopy in the infrared, visible, and ultraviolet regions of the spectrum, and because it has no electric-dipole-allowed vibrational or rotational transitions, its spectral signature is a sensitive probe of the local environment.Before the work described in this Account, models of C2 photophysics included the thitherto-unobserved c3Σu+ state and parametrized the strength of spin-forbidden intercombination transitions. Furthermore, they did not account for photodissociation of C2, even though it was identified in the 1930s as a key process. Inspired by the observation of C2 in the Red Rectangle nebula, the author was motivated to instill rigor into C2 models and embarked on a spectroscopic and computational journey that has lasted 15 years.We were the first to identify the c3Σu+ state through the d3Πg-c3Σu+ transitions, which were to become known as the "Duck" system. This minor partner to the well-known Swan bands is a key part of astrophysical C2 models and can now be included with rigor. We identified the e3Πg-c3Σu+ system, and the c3Σu+ state is now well-studied. Meanwhile others described the singlet-triplet and triplet-quintet interactions in exquisite detail, allowing rigorous modeling of the a-X and c-X intercombination transitions.The final piece of the C2 puzzle would be understanding how long it survives before being broken into carbon atom fragments. Though predicted by Herzberg, predissociation in the e3Πg state had never been observed. To find it would require the complicated ultraviolet spectroscopy of C2 to be disentangled. In so doing, we identified the 43Πg and 33Πg states of C2, thus uncovering two new band systems. The 43Πg state allowed the first accurate determination of the ionization energy of C2. With these new band systems secure, we extracted new levels of the D1Σu+ state (Mulliken bands) and the e3Πg state (Fox-Herzberg bands) from our spectra. Upon climbing the energy ladder in the e3Πg state to v = 12, we finally identified the route to predissociation of C2 via non-adiabatic coupling to the d3Πg state. This observation provided the first laboratory evidence for why C2 is observed in the coma of a comet but not the tail.
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Affiliation(s)
- Timothy W. Schmidt
- ARC Centre of Excellence in Exciton Science, School of Chemistry, UNSW Sydney, Sydney, NSW 2052, Australia
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3
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Rocha CMR, Varandas AJC. A global CHIPR potential energy surface for ground-state C 3H and exploratory dynamics studies of reaction C 2 + CH → C 3 + H. Phys Chem Chem Phys 2019; 21:24406-24418. [PMID: 31663556 DOI: 10.1039/c9cp04890a] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A full-dimensional global potential-energy surface (PES) is first reported for ground-state doublet C3H using the combined-hyperbolic-inverse-power-representation (CHIPR) method and accurate ab initio energies extrapolated to the complete basis set limit. The PES is based on a many-body expansion-type development where the two-body and three-body energy terms are from our previously reported analytic potentials for C2H(2A') and C3(1A',3A'), while the effective four-body one is calibrated using an extension of the CHIPR formalism for tetratomics. The final form is shown to accurately reproduce all known stationary structures of the PES, some of which are unreported thus far, and their interconversion pathways. Moreover, it warrants by built-in construction the appropriate permutational symmetry and describes in a physically reasonable manner all long-range features and the correct asymptotic behavior at dissociation. Exploratory quasi-classical trajectory calculations for the reaction C2 + CH → C3 + H are also performed, yielding thermalized rate coefficients for temperatures up to 4000 K.
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Affiliation(s)
- C M R Rocha
- Department of Chemistry and Coimbra Chemistry Centre, University of Coimbra, 3004-535 Coimbra, Portugal.
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4
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Rocha CMR, Varandas AJC. Accurate CHIPR Potential Energy Surface for the Lowest Triplet State of C 3. J Phys Chem A 2019; 123:8154-8169. [PMID: 31184891 DOI: 10.1021/acs.jpca.9b03194] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
We report the first global ab initio-based potential energy surface (PES) for ground-state triplet C3(3A') based on accurate energies extrapolated to the complete basis set (CBS) limit, and using the combined-hyperbolic-inverse-power-representation method for the analytical modeling. By relying on a cost-effective CBS(D,T) protocol, we ensure that the final form reproduces all topographical features of the PES, including its cyclic-linear isomerization barrier, with CBS(5,6)-quality. To partially account for the incompleteness of the N-electron basis and other minor effects, the available accurate experimental data on the relevant diatomics were used to obtain direct-fit curves that replace the theoretical ones in the many-body expansion. Besides describing properly long-range interactions at all asymptotic channels and permutational symmetry by built-in construction, the PES reported here reproduces the proper exothermicities at dissociation regions as well as the spectroscopy of the diatomic fragments. Bound vibrational state calculations in both linear and cyclic isomers have also been carried out, unveiling a good match of the available data on C3(ã 3Πu), while assisting with IR band positions for C3(3A2') that may serve as a guide for its laboratory and astronomical detection.
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Affiliation(s)
- C M R Rocha
- Coimbra Chemistry Centre and Chemistry Department , University of Coimbra , 3004-535 Coimbra , Portugal
| | - A J C Varandas
- Coimbra Chemistry Centre and Chemistry Department , University of Coimbra , 3004-535 Coimbra , Portugal.,School of Physics and Physical Engineering , Qufu Normal University , Qufu 273165 , P. R. China
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5
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Visser B, Beck M, Bornhauser P, Knopp G, van Bokhoven JA, Radi P, Gourlaouen C, Marquardt R. New experimental and theoretical assessment of the dissociation energy of C2. Mol Phys 2019. [DOI: 10.1080/00268976.2018.1564849] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Affiliation(s)
| | - Martin Beck
- Paul Scherrer Institute, Villigen, Switzerland
| | | | | | - Jeroen Anton van Bokhoven
- Paul Scherrer Institute, Villigen, Switzerland
- Institute for Chemical and Bioengineering, ETH Zurich, Zurich, Switzerland
| | - Peter Radi
- Paul Scherrer Institute, Villigen, Switzerland
| | - Christophe Gourlaouen
- Laboratoire de Chimie Quantique – Institut de Chimie – UMR 7177 CNRS/Unistra, Université de Strasbourg, Strasbourg, France
| | - Roberto Marquardt
- Laboratoire de Chimie Quantique – Institut de Chimie – UMR 7177 CNRS/Unistra, Université de Strasbourg, Strasbourg, France
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6
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Mullinax JW, Sokolov AY, Schaefer HF. Can density cumulant functional theory describe static correlation effects? J Chem Theory Comput 2016; 11:2487-95. [PMID: 26575548 DOI: 10.1021/acs.jctc.5b00346] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
We evaluate the performance of density cumulant functional theory (DCT) for capturing static correlation effects. In particular, we examine systems with significant multideterminant character of the electronic wave function, such as the beryllium dimer, diatomic carbon, m-benzyne, 2,6-pyridyne, twisted ethylene, as well as the barrier for double-bond migration in cyclobutadiene. We compute molecular properties of these systems using the ODC-12 and DC-12 variants of DCT and compare these results to multireference configuration interaction and multireference coupled-cluster theories, as well as single-reference coupled-cluster theory with single, double (CCSD), and perturbative triple excitations [CCSD(T)]. For all systems the DCT methods show intermediate performance between that of CCSD and CCSD(T), with significant improvement over the former method. In particular, for the beryllium dimer, m-benzyne, and 2,6-pyridyne, the ODC-12 method along with CCSD(T) correctly predict the global minimum structures, while CCSD predictions fail qualitatively, underestimating the multireference effects. Our results suggest that the DC-12 and ODC-12 methods are capable of describing emerging static correlation effects but should be used cautiously when highly accurate results are required. Conveniently, the appearance of multireference effects in DCT can be diagnosed by analyzing the DCT natural orbital occupations, which are readily available at the end of the energy computation.
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Affiliation(s)
- J Wayne Mullinax
- Center for Computational Quantum Chemistry, University of Georgia , Athens, Georgia 30602, United States
| | - Alexander Yu Sokolov
- Center for Computational Quantum Chemistry, University of Georgia , Athens, Georgia 30602, United States.,Department of Chemistry, Princeton University , Princeton, New Jersey 08544, United States
| | - Henry F Schaefer
- Center for Computational Quantum Chemistry, University of Georgia , Athens, Georgia 30602, United States
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7
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Xu LT, Dunning TH. Insights into the Perplexing Nature of the Bonding in C2 from Generalized Valence Bond Calculations. J Chem Theory Comput 2015; 10:195-201. [PMID: 26579902 DOI: 10.1021/ct400867h] [Citation(s) in RCA: 59] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Diatomic carbon, C2, has been variously described as having a double, triple, or quadruple bond. In this article, we report full generalized valence bond (GVB) calculations on C2. The GVB wave function-more accurate than the Hartree-Fock wave function and easier to interpret than traditional multiconfiguration wave functions-is well-suited for characterizing the bonding in C2. The GVB calculations show that the electronic wave function of C2 is not well described by a product of singlet-coupled, shared electron pairs (perfect pairing), which is the theoretical basis for covalent chemical bonds. Rather, C2 is best described as having a traditional covalent σ bond with the electrons in the remaining orbitals of the two carbon atoms antiferromagnetically coupled. However, even this description is incomplete as the perfect pairing spin function also makes a significant contribution to the full GVB wave function. The complicated structure of the wave function of C2 is the source of the uncertainty about the nature of the bonding in this molecule.
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Affiliation(s)
- Lu T Xu
- Department of Chemistry, University of Illinois at Urbana-Champaign , 600 South Mathews Avenue, Urbana, Illinois 61801, United States
| | - Thom H Dunning
- Department of Chemistry, University of Illinois at Urbana-Champaign , 600 South Mathews Avenue, Urbana, Illinois 61801, United States
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8
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Rocha CMR, Varandas AJC. Accurate ab initio-based double many-body expansion potential energy surface for the adiabatic ground-state of the C3 radical including combined Jahn-Teller plus pseudo-Jahn-Teller interactions. J Chem Phys 2015; 143:074302. [DOI: 10.1063/1.4928434] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Affiliation(s)
- C. M. R. Rocha
- Departamento de Química, and Centro de Química, Universidade de Coimbra, 3004-535 Coimbra, Portugal
| | - A. J. C. Varandas
- Departamento de Química, and Centro de Química, Universidade de Coimbra, 3004-535 Coimbra, Portugal
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9
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Krechkivska O, Bacskay GB, Troy TP, Nauta K, Kreuscher TD, Kable SH, Schmidt TW. Resonance-Enhanced 2-Photon Ionization Scheme for C2 through a Newly Identified Band System: 43Πg–a3Πu. J Phys Chem A 2015; 119:12102-8. [DOI: 10.1021/acs.jpca.5b05685] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
| | - George B. Bacskay
- School
of Chemistry, The University of Sydney, Sydney, NSW 2006, Australia
| | - Tyler P. Troy
- School
of Chemistry, The University of Sydney, Sydney, NSW 2006, Australia
- Advanced
Light Source, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
| | - Klaas Nauta
- School
of Chemistry, UNSW, Sydney, NSW 2052, Australia
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10
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Hu X, Xie C, Xie D. State-to-state quantum dynamics of the N(4S) + C2( $$\tilde{X}$$ X ~ 1Σ+) → CN( $$\tilde{X}$$ X ~ 2Σ+) + C(3P) reaction. Theor Chem Acc 2014. [DOI: 10.1007/s00214-014-1529-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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11
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Tecmer P, Boguslawski K, Johnson PA, Limacher PA, Chan M, Verstraelen T, Ayers PW. Assessing the Accuracy of New Geminal-Based Approaches. J Phys Chem A 2014; 118:9058-68. [PMID: 24745368 DOI: 10.1021/jp502127v] [Citation(s) in RCA: 60] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Affiliation(s)
- Paweł Tecmer
- Department
of Chemistry and Chemical Biology, McMaster University, 1280 Main
Street West, L8S 4M1, Hamilton, Ontario, Canada
| | - Katharina Boguslawski
- Department
of Chemistry and Chemical Biology, McMaster University, 1280 Main
Street West, L8S 4M1, Hamilton, Ontario, Canada
| | - Paul A. Johnson
- Department
of Chemistry and Chemical Biology, McMaster University, 1280 Main
Street West, L8S 4M1, Hamilton, Ontario, Canada
| | - Peter A. Limacher
- Department
of Chemistry and Chemical Biology, McMaster University, 1280 Main
Street West, L8S 4M1, Hamilton, Ontario, Canada
| | - Matthew Chan
- Department
of Chemistry and Chemical Biology, McMaster University, 1280 Main
Street West, L8S 4M1, Hamilton, Ontario, Canada
| | - Toon Verstraelen
- Center
for Molecular Modeling, QCMM Alliance Ghent-Brussels, Ghent University, Technologiepark
903, Zwijnaarde 9052, Belgium
| | - Paul W. Ayers
- Department
of Chemistry and Chemical Biology, McMaster University, 1280 Main
Street West, L8S 4M1, Hamilton, Ontario, Canada
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12
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Du J, Sun X, Chen J, Jiang G. Understanding the stability, bonding nature and chemical reactivity of 3d-substituted heterofullerenes C58TM (TM = Sc–Zn) from DFT studies. RSC Adv 2014. [DOI: 10.1039/c4ra04139a] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
A systematic DFT study for the stability, bonding nature and reactivity of 3d-substituted heterofullerenes C58TM (TM = Sc–Zn).
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Affiliation(s)
- Jiguang Du
- College of Physical Science and Technology
- Sichuan University
- Chengdu 610064, China
| | - Xiyuan Sun
- College of Science
- Sichuan Agricultural University
- Ya'an 625014, China
| | - Jun Chen
- State Key Laboratory of Surface Physics and Chemistry
- Mianyang, China
| | - Gang Jiang
- Institute of Atomic and Molecular Physics
- Sichuan University
- Chengdu 610065, China
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13
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Boschen JS, Theis D, Ruedenberg K, Windus TL. Accurate ab initio potential energy curves and spectroscopic properties of the four lowest singlet states of C2. Theor Chem Acc 2013. [DOI: 10.1007/s00214-013-1425-x] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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14
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Roskop LB, Kong L, Valeev EF, Gordon MS, Windus TL. Assessment of Perturbative Explicitly Correlated Methods for Prototypes of Multiconfiguration Electronic Structure. J Chem Theory Comput 2013; 10:90-101. [PMID: 26579894 DOI: 10.1021/ct4006773] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Luke B Roskop
- Department of Chemistry, Iowa State University , Ames, Iowa 50010, United States
| | - Liguo Kong
- Department of Chemistry, Virginia Tech , Blacksburg, Virginia 24061, United States
| | - Edward F Valeev
- Department of Chemistry, Virginia Tech , Blacksburg, Virginia 24061, United States
| | - Mark S Gordon
- Department of Chemistry, Iowa State University , Ames, Iowa 50010, United States
| | - Theresa L Windus
- Department of Chemistry, Iowa State University , Ames, Iowa 50010, United States
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15
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Ruscic B, Feller D, Peterson KA. Active Thermochemical Tables: dissociation energies of several homonuclear first-row diatomics and related thermochemical values. Theor Chem Acc 2013. [DOI: 10.1007/s00214-013-1415-z] [Citation(s) in RCA: 56] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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16
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Xu J, Deible MJ, Peterson KA, Jordan KD. Correlation Consistent Gaussian Basis Sets for H, B–Ne with Dirac–Fock AREP Pseudopotentials: Applications in Quantum Monte Carlo Calculations. J Chem Theory Comput 2013; 9:2170-8. [DOI: 10.1021/ct300983b] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Affiliation(s)
- Jiawei Xu
- Department of Chemistry, University of Pittsburgh, Pittsburgh, Pennsylvania
15218, United States
| | - Michael J. Deible
- Department of Chemistry, University of Pittsburgh, Pittsburgh, Pennsylvania
15218, United States
| | - Kirk A. Peterson
- Department
of Chemistry, Washington State University, Pullman, Washington 99164,
United States
| | - Kenneth D. Jordan
- Department of Chemistry, University of Pittsburgh, Pittsburgh, Pennsylvania
15218, United States
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18
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Shi D, Zhang X, Sun J, Zhu Z. MRCI study on spectroscopic and molecular properties of B1Δg, , C1Πg, , and 11Δuelectronic states of the C2radical. Mol Phys 2011. [DOI: 10.1080/00268976.2011.564593] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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19
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Joseph S, Varandas AJC. Ab initio Based DMBE Potential Energy Surface for the Ground Electronic State of the C2H Molecule. J Phys Chem A 2010; 114:2655-64. [DOI: 10.1021/jp910269w] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- S. Joseph
- Departamento de Química, Universidade de Coimbra, 3004-535 Coimbra, Portugal
| | - A. J. C. Varandas
- Departamento de Química, Universidade de Coimbra, 3004-535 Coimbra, Portugal
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20
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Bajdich M, Kolorenč J, Mitas L, Reynolds P. Pairing in Cold Atoms and other Applications for Quantum Monte Carlo methods. ACTA ACUST UNITED AC 2010. [DOI: 10.1016/j.phpro.2010.01.199] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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21
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Qu Y, Su K, Wang X, Liu Y, Zeng Q, Cheng L, Zhang L. Reaction pathways of propene pyrolysis. J Comput Chem 2010; 31:1421-42. [DOI: 10.1002/jcc.21427] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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22
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BOGGIO-PASQUA M, VORONIN AI, HALVICK PH, RAYEZ JC, VARANDAS AJC. Coupled ab initio potential energy surfaces for the two lowest 2A′ electronic states of the C2H molecule. Mol Phys 2009. [DOI: 10.1080/00268970009483396] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Affiliation(s)
- M. BOGGIO-PASQUA
- a Laboratoire de Physico-Chimie Moléculaire—UMR 5803/CNRS , Université Bordeaux 1 , 33405 , Talence Cedex, France
| | - A. I. VORONIN
- a Laboratoire de Physico-Chimie Moléculaire—UMR 5803/CNRS , Université Bordeaux 1 , 33405 , Talence Cedex, France
| | - PH. HALVICK
- a Laboratoire de Physico-Chimie Moléculaire—UMR 5803/CNRS , Université Bordeaux 1 , 33405 , Talence Cedex, France
| | - J.-C. RAYEZ
- a Laboratoire de Physico-Chimie Moléculaire—UMR 5803/CNRS , Université Bordeaux 1 , 33405 , Talence Cedex, France
| | - A. J. C. VARANDAS
- b Departamento de Química , Universidade de Coimbra , 3049 , Coimbra Codex , Portugal
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23
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Mintz B, Williams TG, Howard L, Wilson AK. Computation of potential energy surfaces with the multireference correlation consistent composite approach. J Chem Phys 2009; 130:234104. [DOI: 10.1063/1.3149387] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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24
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25
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26
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Varandas AJC. Extrapolation to the complete-basis-set limit and the implications of avoided crossings: The X Σ1g+, B Δ1g, and B′ Σ1g+ states of C2. J Chem Phys 2008; 129:234103. [DOI: 10.1063/1.3036115] [Citation(s) in RCA: 59] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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27
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Domin D, Braïda B, Lester Jr. WA. Breathing Orbital Valence Bond Method in Diffusion Monte Carlo: C−H Bond Dissociation of Acetylene. J Phys Chem A 2008; 112:8964-9. [DOI: 10.1021/jp8020062] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Dominik Domin
- Kenneth S. Pitzer Center for Theoretical Chemistry, Department of Chemistry, University of California at Berkeley, Berkeley, California 94720-1460, UPMC Université Paris 06, UMR 7616, Laboratoire de Chimie Théorique, Case courrier 137 4 place Jussieu, 75005, Paris, France, CNRS Centre National de la Recherche Scientifique, UMR 7616, 75252 Paris, France, and Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720
| | - Benoît Braïda
- Kenneth S. Pitzer Center for Theoretical Chemistry, Department of Chemistry, University of California at Berkeley, Berkeley, California 94720-1460, UPMC Université Paris 06, UMR 7616, Laboratoire de Chimie Théorique, Case courrier 137 4 place Jussieu, 75005, Paris, France, CNRS Centre National de la Recherche Scientifique, UMR 7616, 75252 Paris, France, and Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720
| | - William A. Lester Jr.
- Kenneth S. Pitzer Center for Theoretical Chemistry, Department of Chemistry, University of California at Berkeley, Berkeley, California 94720-1460, UPMC Université Paris 06, UMR 7616, Laboratoire de Chimie Théorique, Case courrier 137 4 place Jussieu, 75005, Paris, France, CNRS Centre National de la Recherche Scientifique, UMR 7616, 75252 Paris, France, and Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720
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28
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Tuna T, Chabot M, Pino T, Désesquelles P, LePadellec A, Martinet G, Barat M, Lucas B, Mezdari F, Montagnon L, Van-Oanh NT, Lavergne L, Lachaize A, Carpentier Y, Béroff K. Fragmentation branching ratios of highly excited hydrocarbon molecules CnH and their cations CnH+ (n⩽4). J Chem Phys 2008; 128:124312. [DOI: 10.1063/1.2884862] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
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29
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Shi Y, Ervin KM. Hydrogen Atom Transfer Reactions of C2-, C4-, and C6-: Bond Dissociation Energies of Linear H−C2n- and H−C2n (n = 1, 2, 3). J Phys Chem A 2008; 112:1261-7. [DOI: 10.1021/jp077181c] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Yang Shi
- Department of Chemistry and Chemical Physics Program, University of Nevada, Reno, 1664 North Virginia Street, Reno, Nevada 89557-0216
| | - Kent M. Ervin
- Department of Chemistry and Chemical Physics Program, University of Nevada, Reno, 1664 North Virginia Street, Reno, Nevada 89557-0216
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Corongiu G. Multiple Bonds and Excited States from the Hartree−Fock−Heitler−London Method. J Phys Chem A 2007; 111:13611-22. [DOI: 10.1021/jp0748056] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Affiliation(s)
- Giorgina Corongiu
- Dipartimento di Scienze Chimiche ed Ambientali, Università dell'Insubria, Via Lucini 3, I-22100 Como, Italy
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31
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Feller D, Peterson KA. Probing the limits of accuracy in electronic structure calculations: Is theory capable of results uniformly better than “chemical accuracy”? J Chem Phys 2007; 126:114105. [PMID: 17381194 DOI: 10.1063/1.2464112] [Citation(s) in RCA: 82] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
Current limitations in electronic structure methods are discussed from the perspective of their potential to contribute to inherent uncertainties in predictions of molecular properties, with an emphasis on atomization energies (or heats of formation). The practical difficulties arising from attempts to achieve high accuracy are illustrated via two case studies: the carbon dimer (C2) and the hydroperoxyl radical (HO2). While the HO2 wave function is dominated by a single configuration, the carbon dimer involves considerable multiconfigurational character. In addition to these two molecules, statistical results will be presented for a much larger sample of molecules drawn from the Computational Results Database. The goal of this analysis will be to determine if a combination of coupled cluster theory with large 1-particle basis sets and careful incorporation of several computationally expensive smaller corrections can yield uniform agreement with experiment to better than "chemical accuracy" (+/-1 kcal/mol). In the case of HO2, the best current theoretical estimate of the zero-point-inclusive, spin-orbit corrected atomization energy (SigmaD0=166.0+/-0.3 kcal/mol) and the most recent Active Thermochemical Table (ATcT) value (165.97+/-0.06 kcal/mol) are in excellent agreement. For C2 the agreement is only slightly poorer, with theory (D0=143.7+/-0.3 kcal/mol) almost encompassing the most recent ATcT value (144.03+/-0.13 kcal/mol). For a larger collection of 68 molecules, a mean absolute deviation of 0.3 kcal/mol was found. The same high level of theory that produces good agreement for atomization energies also appears capable of predicting bond lengths to an accuracy of +/-0.001 A.
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Affiliation(s)
- David Feller
- Department of Chemistry, Washington State University, Pullman, Washington 99164-4630, USA.
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32
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Schofield K, Steinberg M. CH and C2 Measurements Imply a Radical Pool within a Pool in Acetylene Flames. J Phys Chem A 2007; 111:2098-114. [PMID: 17388296 DOI: 10.1021/jp0667689] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Measured CH and C2 profiles show a striking resemblance as a function of time in a series of seven well-characterized fuel-rich (phi=1.2-2.0) non-sooting acetylene flames. This implied commonality and interrelationship are unexpected as these radicals have dissimilar chemical kinetic natures. As a result, a rigorous examination was undertaken of the behavior of each of the hydrocarbon species known to be present, C, CH, CH2, CH3, CH4, CHO, CHOH, CH2O, CH2OH, CH3O, CH3OH, C2, C2H, C2H2, CHCO, CH2CO, and C2O. This emphasized the main region where CH and C2 are observed (50-600 micros) and reduced the kinetic reactions to only those that operate efficiently and are dominant. It was immediately apparent that this region of the flame reflects the nature of a hydrogen flame heavily doped with CO and CO2 and containing traces of hydrocarbons. The radical species, H, OH, O, along with H2, H2O, and O2, form an important controlling radical pool that is in partial equilibrium, and the concentrations of each of the hydrocarbon radicals are minor to this, playing secondary roles. As a result, the dominant fast reactions are those between the hydrocarbons and the basic hydrogen/oxygen radicals. Hydrocarbon-hydrocarbon reactions are unimportant here at these equivalence ratios. CH and C2 are formed and destroyed on a sub-microsecond time scale so that their flame profiles are the reflection of a complex kinetically dynamic system. This is found to be the case for all of the hydrocarbon species examined. As might be expected, these rapidly form steady-state distributions. However, with the exceptions of C, CHO, CHOH, and CH2O, which are irreversibly being oxidized, the others all form an interconnected hydrocarbon pool that is under the control of the larger hydrogen radical pool. The hydrocarbon pool can rapidly adjust, and the CH and C2 decay together as the pool is drained. This is either by continuing oxidation in less rich mixtures, or in richer flames where this is negligible by the onset of hydrocarbon-hydrocarbon reactions. The implications of such a hydrocarbon pool are significant. It introduces a buffering effect on their distribution and provides the indirect connection between CH and C2. Moreover, because they are members of this radical pool, flame studies alone cannot answer questions concerning their specific importance in combustion other than their contributing role to this pool. The presence of such a pool modifies the exactness that is needed for kinetic mechanisms, and knowledge of every species in the system no longer is necessary. Furthermore, as rate constants become refined, it will allow for the calculation of the relative concentrations of the hydrocarbon species and facilitate reduced kinetic mechanisms. It provides an explanation for previous isotopically labeled experiments and illustrates the difficulty of exactly identifying in flames the role of individual species. It resolves the fact that differing kinetic models can show similar levels of accuracy and has implications for sensitivity analyses. It finally unveils the mechanism of the flame ionization detector and has implications for the differing interpretations of diamond formation mechanisms.
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Affiliation(s)
- Keith Schofield
- Materials Research Laboratory, University of California, Santa Barbara, California 93106-5121, USA.
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33
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Grant DJ, Dixon DA. Sigma- and pi-bond strengths in main group 3-5 compounds. J Phys Chem A 2007; 110:12955-62. [PMID: 17125312 DOI: 10.1021/jp065085q] [Citation(s) in RCA: 85] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
The sigma- and pi-bond strengths for the molecules BH2NH2, BH2PH2, AlH2NH2, and AlH2PH2 have been calculated by using ab initio molecular electronic structure theory at the CCSD(T)/CBS level. The adiabatic pi-bond energy is defined as the rotation barrier between the equilibrium ground-state configuration and the C(s)symmetry transition state for torsion about the A-X bond. We also report intrinsic pi-bond energies corresponding to the adiabatic rotation barrier corrected for the inversion barrier at N or P. The adiabatic sigma-bond energy is defined as the dissociation energy of AH2XH2 to AH2 + XH2 in their ground states minus the adiabatic pi-bond energy. The adiabatic sigma-bond strengths for the molecules BH2NH2, BH2PH2, AlH2NH2, and AlH2PH2 are 109.8, 98.8, 77.6, and 68.3 kcal/mol, respectively, and the corresponding adiabatic pi-bond strengths are 29.9, 10.5, 9.2, and 2.7 kcal/mol, respectively.
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Affiliation(s)
- Daniel J Grant
- Department of Chemistry, Shelby Hall, The University of Alabama, P.O. Box 870336, Tuscaloosa, AL 35487-0336, USA
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35
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Bytautas L, Ruedenberg K. Correlation energy extrapolation by intrinsic scaling. IV. Accurate binding energies of the homonuclear diatomic molecules carbon, nitrogen, oxygen, and fluorine. J Chem Phys 2005; 122:154110. [PMID: 15945628 DOI: 10.1063/1.1869493] [Citation(s) in RCA: 93] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
The method of extrapolation by intrinsic scaling, recently introduced to obtain correlation energies, is generalized to multiconfigurational reference functions and used to calculate the binding energies of the diatomic molecules C2, N2, O2, and F2. First, accurate approximations to the full configuration interaction energies of the individual molecules and their constituent atoms are determined, employing Dunning's correlation consistent double-, triple- and quadruple zeta basis sets. Then, these energies are extrapolated to their full basis set limits. Chemical accuracy is attained for the binding energies of all molecules.
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Affiliation(s)
- Laimutis Bytautas
- Department of Chemistry and Ames Laboratory USDOE, Iowa State University, Ames, Iowa 50011, USA
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37
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Feller D, Dixon DA. Coupled Cluster Theory and Multireference Configuration Interaction Study of FO, F2O, FO2, and FOOF. J Phys Chem A 2003. [DOI: 10.1021/jp030267v] [Citation(s) in RCA: 82] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- David Feller
- Chemical Sciences Division and, Fundamental Sciences Directorate, Pacific Northwest National Laboratory, MS K1-83, P.O. Box 999, Richland, Washington 99352
| | - David A. Dixon
- Chemical Sciences Division and, Fundamental Sciences Directorate, Pacific Northwest National Laboratory, MS K1-83, P.O. Box 999, Richland, Washington 99352
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38
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Dı́az-Tendero S, Alcamı́ M, Martı́n F. Theoretical study of ionization potentials and dissociation energies of Cnq+ fullerenes (n=50–60, q=0, 1 and 2). J Chem Phys 2003. [DOI: 10.1063/1.1597634] [Citation(s) in RCA: 75] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
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39
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Meloni G, Thomson LM, Gingerich KA. Structure and thermodynamic stability of the OsC and OsC2 molecules by theoretical calculations and by Knudsen cell mass spectrometry. J Chem Phys 2001. [DOI: 10.1063/1.1390504] [Citation(s) in RCA: 30] [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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40
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Mebel AM, Hayashi M, Jackson WM, Wrobel J, Green M, Xu D, Lin SH. Branching ratios of C2 products in the photodissociation of C2H at 193 nm. J Chem Phys 2001. [DOI: 10.1063/1.1370942] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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41
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Császár AG, Leininger ML. Scaled higher-order correlation energies: In pursuit of the complete basis set full configuration interaction limit. J Chem Phys 2001. [DOI: 10.1063/1.1351882] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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42
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Sordo JA. Performance of CCSDT for first row AB/AB− diatomics: Dissociation energies and electron affinities. J Chem Phys 2001. [DOI: 10.1063/1.1335617] [Citation(s) in RCA: 51] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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43
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Barnett RN, Sun Z, Lester WA. Improved trial wave functions in quantum Monte Carlo: Application to acetylene and its dissociation fragments. J Chem Phys 2001. [DOI: 10.1063/1.1335596] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Tzeli D, Mavridis A. First-Principles Investigation of the Boron and Aluminum Carbides BC and AlC and Their Anions BC- and AlC-. 1. J Phys Chem A 2001. [DOI: 10.1021/jp003258k] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Demeter Tzeli
- Laboratory of Physical Chemistry, Department of Chemistry, National and Kapodistrian University of Athens, P.O. Box 64 004, 157 10 Zografou, Athens, Greece
| | - Aristides Mavridis
- Laboratory of Physical Chemistry, Department of Chemistry, National and Kapodistrian University of Athens, P.O. Box 64 004, 157 10 Zografou, Athens, Greece
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45
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Lüchow A, Fink RF. On the systematic improvement of fixed-node diffusion quantum Monte Carlo energies using pair natural orbital CI guide functions. J Chem Phys 2000. [DOI: 10.1063/1.1318748] [Citation(s) in RCA: 26] [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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46
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Boggio-Pasqua M, Voronin A, Halvick P, Rayez JC. Analytical representations of high level ab initio potential energy curves of the C 2 molecule. ACTA ACUST UNITED AC 2000. [DOI: 10.1016/s0166-1280(00)00442-5] [Citation(s) in RCA: 42] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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47
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Chiang WY, Hsu YC. Fluorescence lifetimes and predissociation processes in the B̃ 2A′ state of CCH. J Chem Phys 2000. [DOI: 10.1063/1.481339] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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49
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Affiliation(s)
| | - Alessandra Ricca
- Mail Stop 230-3, NASA Ames Research Center, Moffett Field, California 94035
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50
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Lu W, Tosi P, Filippi M, Bassi D. Reactions of C+(2Pu) with CO(1Σ+) from thermal energies to 30 eV. J Chem Phys 2000. [DOI: 10.1063/1.480686] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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