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Battaglia S, Fransén L, Fdez Galván I, Lindh R. Regularized CASPT2: an Intruder-State-Free Approach. J Chem Theory Comput 2022; 18:4814-4825. [PMID: 35876618 PMCID: PMC9367007 DOI: 10.1021/acs.jctc.2c00368] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
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In this work we present a new approach to fix the intruder-state
problem (ISP) in CASPT2 based on σp regularization. The resulting σp-CASPT2 method is compared to previous techniques, namely, the real
and imaginary level shifts, on a theoretical basis and by performing
a series of systematic calculations. The analysis is focused on two
aspects, the effectiveness of σp-CASPT2 in removing the ISP and the sensitivity of the approach with
respect to the input parameter. We found that σp-CASPT2 compares favorably with respect to previous
approaches and that different versions, σ1-CASPT2
and σ2-CASPT2, have different potential application
domains. This analysis also reveals the unsuitability of the real
level shift technique as a general way to avoid the intruder-state
problem.
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Affiliation(s)
- Stefano Battaglia
- Department of Chemistry─BMC, Uppsala University, P. O. Box 576, SE-75123 Uppsala, Sweden
| | - Lina Fransén
- Department of Chemistry─BMC, Uppsala University, P. O. Box 576, SE-75123 Uppsala, Sweden
| | - Ignacio Fdez Galván
- Department of Chemistry─BMC, Uppsala University, P. O. Box 576, SE-75123 Uppsala, Sweden
| | - Roland Lindh
- Department of Chemistry─BMC, Uppsala University, P. O. Box 576, SE-75123 Uppsala, Sweden
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2
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Ivanov AV, Ghosh TK, Jónsson EÖ, Jónsson H. Mn Dimer Can Be Described Accurately with Density Functional Calculations When Self-Interaction Correction Is Applied. J Phys Chem Lett 2021; 12:4240-4246. [PMID: 33900768 DOI: 10.1021/acs.jpclett.1c00364] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Qualitatively incorrect results are obtained for the Mn dimer in density functional theory calculations using the generalized gradient approximation (GGA), and similar results are obtained from local density and meta-GGA functionals. The coupling is predicted to be ferromagnetic rather than antiferromagnetic, and the bond between the atoms is predicted to be an order of magnitude too strong and approximately an Ångstrøm too short. Explicit, self-interaction correction (SIC) applied to a commonly used GGA energy functional, however, provides close agreement with both experimental data and high-level, multireference wave function calculations. These results show that the failure is not due to a strong correlation but rather the single electron self-interaction that is necessarily introduced in estimates of the classical Coulomb and exchange-correlation energy when only the total electron density is used as the input. The corrected functional depends explicitly on the orbital densities and can, therefore, avoid the introduction of a self-Coulomb interaction. The error arises because of an overstabilization of bonding d-states in the minority spin channel resulting from an overestimate of the d-electron self-interaction in the semilocal exchange-correlation functionals. Since the computational effort in the SIC calculations scales with the system size in the same way as for regular semilocal functional calculations, this approach provides a way to calculate properties of Mn nanoclusters as well as biomolecules and extended solids, where Mn dimers and larger cluster are present, while multireference wave function calculations can only be applied to small systems.
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Affiliation(s)
- Aleksei V Ivanov
- Science Institute and Faculty of Physical Sciences, University of Iceland VR-III, 107 Reykjavík, Reykjavik, Iceland
- St. Petersburg State University, St. Petersburg 199034, Russia
| | - Tushar K Ghosh
- Science Institute and Faculty of Physical Sciences, University of Iceland VR-III, 107 Reykjavík, Reykjavik, Iceland
- Department of Applied Physics, Aalto University, Espoo FI-00076, Finland
| | - Elvar Ö Jónsson
- Science Institute and Faculty of Physical Sciences, University of Iceland VR-III, 107 Reykjavík, Reykjavik, Iceland
- Department of Applied Physics, Aalto University, Espoo FI-00076, Finland
| | - Hannes Jónsson
- Science Institute and Faculty of Physical Sciences, University of Iceland VR-III, 107 Reykjavík, Reykjavik, Iceland
- Department of Applied Physics, Aalto University, Espoo FI-00076, Finland
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3
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Chattopadhyay S. Ab Initio Probing of the Ground State of Tetraradicals: Breakdown of Hund's Multiplicity Rule. J Phys Chem A 2019; 123:2211-2226. [PMID: 30794415 DOI: 10.1021/acs.jpca.8b10514] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The electronic structure of organic σ-type polyradical including 2,4,6-tridehydropyridine radical cation (246-TDHP) and three isomers of tetradehydrobenzene (TDHB) have been studied using a computationally robust and cost-effective second-order multireference perturbative model which provides a balanced treatment of nondynamic and dynamic contributions to the electron correlation problem in the ground or excited electronic states which are imperative for predicting structural properties (e.g., ground state multiplicity, energy gaps between high-spin and low-spin states, etc.) of polyradicals. Energy gaps are useful to capture insight into the degree of interaction between the radical sites. An important finding of this study is that the tetraradicals considered here possess singlet ground states, contrary to Hund's rule. Present findings are in close agreement with the available high-level ab initio estimates at attainable cost implying that a perturbative description of the systems is adequate. The impact of N+ on the nature of ground state for the 246-TDHP have also analyzed. The singlet-triplet energy gaps for 1245- and 1234-TDHB are smaller than for o-benzyne mainly due to the ring strain. 1235-TDHB is 14.42 and 11.05 kcal/mol lower in energy than 1245- and 1234-isomers, respectively. IVO-SSMRPT predicts 1A1-3B2 and 1A1-5B2 gaps of 25.84 and 105.15 kcal/mol, respectively for the 246-TDHP cation.
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Affiliation(s)
- Sudip Chattopadhyay
- Department of Chemistry , Indian Institute of Engineering Science and Technology , Shibpur , Howrah 711103 , India
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4
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Chattopadhyay S. Description of quasidegenerate electronic states exhibiting avoided crossing. Mol Phys 2018. [DOI: 10.1080/00268976.2018.1483538] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/14/2022]
Affiliation(s)
- Sudip Chattopadhyay
- Department of Chemistry, Indian Institute of Engineering Science and Technology, Shibpur, India
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5
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Patkowski K, Żuchowski PS, Smith DGA. First-order symmetry-adapted perturbation theory for multiplet splittings. J Chem Phys 2018; 148:164110. [PMID: 29716224 DOI: 10.1063/1.5021891] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
We present a symmetry-adapted perturbation theory (SAPT) for the interaction of two high-spin open-shell molecules (described by their restricted open-shell Hartree-Fock determinants) resulting in low-spin states of the complex. The previously available SAPT formalisms, except for some system-specific studies for few-electron complexes, were restricted to the high-spin state of the interacting system. Thus, the new approach provides, for the first time, a SAPT-based estimate of the splittings between different spin states of the complex. We have derived and implemented the lowest-order SAPT term responsible for these splittings, that is, the first-order exchange energy. We show that within the so-called S2 approximation commonly used in SAPT (neglecting effects that vanish as fourth or higher powers of intermolecular overlap integrals), the first-order exchange energies for all multiplets are linear combinations of two matrix elements: a diagonal exchange term that determines the spin-averaged effect and a spin-flip term responsible for the splittings between the states. The numerical factors in this linear combination are determined solely by the Clebsch-Gordan coefficients: accordingly, the S2 approximation implies a Heisenberg Hamiltonian picture with a single coupling strength parameter determining all the splittings. The new approach is cast into both molecular-orbital and atomic-orbital expressions: the latter enable an efficient density-fitted implementation. We test the newly developed formalism on several open-shell complexes ranging from diatomic systems (Li⋯H, Mn⋯Mn, …) to the phenalenyl dimer.
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Affiliation(s)
- Konrad Patkowski
- Department of Chemistry and Biochemistry, Auburn University, Auburn, Alabama 36849, USA
| | - Piotr S Żuchowski
- Institute of Physics, Faculty of Physics, Astronomy and Informatics, Nicolaus Copernicus University, Grudziadzka 5, Torun 87-100, Poland
| | - Daniel G A Smith
- Department of Chemistry and Biochemistry, Auburn University, Auburn, Alabama 36849, USA
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6
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Kleshchina NN, Korchagina KA, Bezrukov DS, Buchachenko AA. Modeling of Manganese Atom and Dimer Isolated in Solid Rare Gases: Structure, Stability, and Effect on Spin Coupling. J Phys Chem A 2017; 121:2429-2441. [PMID: 28263615 DOI: 10.1021/acs.jpca.6b12444] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Structures and energies of the trapping sites of manganese atom and dimer in solid Ar, Kr, and Xe are investigated within the classical model, which balances local distortion and long-range crystal order of the host and provides a means to estimate the relative site stabilities. The model is implemented with the additive pairwise potential field based on the ab initio and best empirical interatomic potential functions. In agreement with experiment, Mn single substitution (SS) and tetrahedral vacancy (TV) occupation are identified as stable for Ar and Kr, whereas the SS site is only found for Xe. Stable trapping sites of the weakly bound Mn2 dimer are shown to be the mergers of SS and/or TV atomic sites. For Ar, (SS + SS) and (TV + TV) sites are close in energy, whereas (SS + TV) site lies higher. The (SS + SS) accommodation is identified as the only stable site in Kr and Xe at low energies. The results are compared with the resonance Raman, electron spin resonance, and absorption spectroscopy data. Reproducing the numbers of stable sites, the calculations tend to underestimate the matrix effect on the dimer vibrational frequency and spin-spin coupling constant. Nonetheless, the level of agreement is found to be informative for tentative assignments of the complex features seen in Mn2 matrix isolation spectroscopy.
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Affiliation(s)
- Nadezhda N Kleshchina
- Department of Chemistry, M. V. Lomonosov Moscow State University , Moscow 119991, Russia
| | - Kseniia A Korchagina
- Department of Chemistry, M. V. Lomonosov Moscow State University , Moscow 119991, Russia
| | - Dmitry S Bezrukov
- Department of Chemistry, M. V. Lomonosov Moscow State University , Moscow 119991, Russia.,Skolkovo Institute of Science and Technology , Skolkovo Innovation Center, Building 3, Moscow 143026, Russia
| | - Alexei A Buchachenko
- Skolkovo Institute of Science and Technology , Skolkovo Innovation Center, Building 3, Moscow 143026, Russia
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7
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Barborini M. Neutral, Anionic, and Cationic Manganese Dimers through Density Functional Theory. J Phys Chem A 2016; 120:1716-26. [DOI: 10.1021/acs.jpca.5b12169] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Matteo Barborini
- S3 Research Center, CNR-NANO, Via Campi 213/a, 41125 Modena, Italy
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8
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Wang J, Manivasagam S, Wilson AK. Multireference Character for 4d Transition Metal-Containing Molecules. J Chem Theory Comput 2015; 11:5865-72. [DOI: 10.1021/acs.jctc.5b00861] [Citation(s) in RCA: 58] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Jiaqi Wang
- Department of Chemistry and
Center for Advanced Scientific Computing and Modeling (CASCaM), University of North Texas, Denton, Texas 76203-5017, United States
| | - Sivabalan Manivasagam
- Department of Chemistry and
Center for Advanced Scientific Computing and Modeling (CASCaM), University of North Texas, Denton, Texas 76203-5017, United States
| | - Angela K. Wilson
- Department of Chemistry and
Center for Advanced Scientific Computing and Modeling (CASCaM), University of North Texas, Denton, Texas 76203-5017, United States
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9
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Zamudio-Bayer V, Hirsch K, Langenberg A, Kossick M, Ławicki A, Terasaki A, v. Issendorff B, Lau JT. Direct observation of high-spin states in manganese dimer and trimer cations by x-ray magnetic circular dichroism spectroscopy in an ion trap. J Chem Phys 2015; 142:234301. [DOI: 10.1063/1.4922487] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- V. Zamudio-Bayer
- Physikalisches Institut, Universität Freiburg, Stefan-Meier-Straße 21, 79104 Freiburg, Germany
- Institut für Methoden und Instrumentierung der Forschung mit Synchrotronstrahlung, Helmholtz-Zentrum Berlin für Materialien und Energie GmbH, Albert-Einstein-Straße 15, 12489 Berlin, Germany
| | - K. Hirsch
- Institut für Methoden und Instrumentierung der Forschung mit Synchrotronstrahlung, Helmholtz-Zentrum Berlin für Materialien und Energie GmbH, Albert-Einstein-Straße 15, 12489 Berlin, Germany
- Institut für Optik und Atomare Physik, Technische Universität Berlin, Hardenbergstraße 36, 10623 Berlin, Germany
| | - A. Langenberg
- Institut für Methoden und Instrumentierung der Forschung mit Synchrotronstrahlung, Helmholtz-Zentrum Berlin für Materialien und Energie GmbH, Albert-Einstein-Straße 15, 12489 Berlin, Germany
- Institut für Optik und Atomare Physik, Technische Universität Berlin, Hardenbergstraße 36, 10623 Berlin, Germany
| | - M. Kossick
- Institut für Methoden und Instrumentierung der Forschung mit Synchrotronstrahlung, Helmholtz-Zentrum Berlin für Materialien und Energie GmbH, Albert-Einstein-Straße 15, 12489 Berlin, Germany
- Institut für Optik und Atomare Physik, Technische Universität Berlin, Hardenbergstraße 36, 10623 Berlin, Germany
| | - A. Ławicki
- Institut für Methoden und Instrumentierung der Forschung mit Synchrotronstrahlung, Helmholtz-Zentrum Berlin für Materialien und Energie GmbH, Albert-Einstein-Straße 15, 12489 Berlin, Germany
| | - A. Terasaki
- Cluster Research Laboratory, Toyota Technological Institute, 717-86 Futamata, Ichikawa, Chiba 272-0001, Japan
- Department of Chemistry, Kyushu University, 6-10-1 Hakozaki, Higashi-ku, Fukuoka 812-8581, Japan
| | - B. v. Issendorff
- Physikalisches Institut, Universität Freiburg, Stefan-Meier-Straße 21, 79104 Freiburg, Germany
| | - J. T. Lau
- Institut für Methoden und Instrumentierung der Forschung mit Synchrotronstrahlung, Helmholtz-Zentrum Berlin für Materialien und Energie GmbH, Albert-Einstein-Straße 15, 12489 Berlin, Germany
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10
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Zamudio-Bayer V, Hirsch K, Langenberg A, Niemeyer M, Vogel M, Ławicki A, Terasaki A, Lau JT, von Issendorff B. Nachweis maximaler Spinpolarisation in Chromdimerkationen durch zirkularen magnetischen Röntgendichroismus. Angew Chem Int Ed Engl 2015. [DOI: 10.1002/ange.201411018] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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11
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Zamudio-Bayer V, Hirsch K, Langenberg A, Niemeyer M, Vogel M, Ławicki A, Terasaki A, Lau JT, von Issendorff B. Maximum Spin Polarization in Chromium Dimer Cations as Demonstrated by X-ray Magnetic Circular Dichroism Spectroscopy. Angew Chem Int Ed Engl 2015; 54:4498-501. [DOI: 10.1002/anie.201411018] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2014] [Revised: 12/11/2014] [Indexed: 11/06/2022]
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12
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Kaplan IG, Miranda U. Multi-reference Ab initio calculations of 3d transition-metal dimers: Sc2. RUSSIAN JOURNAL OF PHYSICAL CHEMISTRY A 2014. [DOI: 10.1134/s0036024414110089] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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13
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Kim J, Kim J. Density functional and multireference ab initio study of the ground and excited states of Ru2. Chem Phys Lett 2014. [DOI: 10.1016/j.cplett.2013.12.002] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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14
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Chang SW, Witek HA. Choice of Optimal Shift Parameter for the Intruder State Removal Techniques in Multireference Perturbation Theory. J Chem Theory Comput 2012; 8:4053-61. [DOI: 10.1021/ct2006924] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Shu-Wei Chang
- Department of Applied Chemistry and Institute of Molecular
Science, National Chiao Tung University, Hsinchu, Taiwan
| | - Henryk A. Witek
- Department of Applied Chemistry and Institute of Molecular
Science, National Chiao Tung University, Hsinchu, Taiwan
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15
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Tamukong PK, Theis D, Khait YG, Hoffmann MR. GVVPT2 Multireference Perturbation Theory Description of Diatomic Scandium, Chromium, and Manganese. J Phys Chem A 2012; 116:4590-601. [PMID: 22512304 DOI: 10.1021/jp300401u] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Patrick K. Tamukong
- Chemistry
Department, University of North Dakota, Grand Forks, North Dakota 58202, United States
| | - Daniel Theis
- Chemistry
Department, University of North Dakota, Grand Forks, North Dakota 58202, United States
| | - Yuriy G. Khait
- Chemistry
Department, University of North Dakota, Grand Forks, North Dakota 58202, United States
| | - Mark R. Hoffmann
- Chemistry
Department, University of North Dakota, Grand Forks, North Dakota 58202, United States
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Camacho C, Cimiraglia R, Witek HA. Reply to the ‘Comment on “Multiconfigurational perturbation theory can predict a false ground state”’ by J. Soto, F. Avila, J. C. Otero and J. F. Arenas, Phys. Chem. Chem. Phys., 2011, DOI: 10.1039/C0CP01917H. Phys Chem Chem Phys 2011. [DOI: 10.1039/c1cp20177h] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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17
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Camacho C, Witek HA, Cimiraglia R. The low-lying states of the scandium dimer. J Chem Phys 2010; 132:244306. [DOI: 10.1063/1.3442374] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
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Camacho C, Cimiraglia R, Witek HA. Multireference perturbation theory can predict a false ground state. Phys Chem Chem Phys 2010; 12:5058-60. [PMID: 20445908 DOI: 10.1039/c000196a] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Prediction of a false ground state with popular variants of multireference perturbation theory (CASPT2 and MRMP) is reported for a remarkably simple chemical system: the Sc(2) molecule.
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Affiliation(s)
- Cristopher Camacho
- Institute of Molecular Science and Department of Applied Chemistry, National Chiao Tung University, 1001 Ta-Hsueh Road, Hsinchu 30010, Taiwan
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19
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Buchachenko AA, Chałasiński G, Szczęśniak MM. Electronic structure and spin coupling of the manganese dimer: The state of the art of ab initio approach. J Chem Phys 2010; 132:024312. [DOI: 10.1063/1.3292572] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.6] [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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Buchachenko AA, Chałasiński G, Szcześniak MM. Europium dimer: van der Waals molecule with extremely weak antiferromagnetic spin coupling. J Chem Phys 2009; 131:241102. [PMID: 20059044 DOI: 10.1063/1.3282332] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
High-level ab initio calculations reveal that the Eu(2) dimer is a van der Waals molecule with extremely weak antiferromagnetic spin coupling. The Heisenberg spin-exchange model, validated by the multireference configuration interaction method, is used to construct the full set of model interaction potentials for the states with the total spin S ranging from 0 to 7 at the coupled cluster level of theory. This model establishes the singlet (1) summation operator(+) (g) state as the ground one of the dimer with the binding energy of 710 cm(-1), the vibrational frequency of 23 cm(-1) and the effective spin-coupling constant J estimated approximately -0.3 cm(-1).
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Vélez E, Alberola A, Polo V. A density functional theory study of the magnetic exchange coupling in dinuclear manganese(II) inverse crown structures. J Phys Chem A 2009; 113:14008-13. [PMID: 20000388 DOI: 10.1021/jp907200u] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
The magnetic exchange coupling constants between two Mn(II) centers for a set of five inverse crown structures have been investigated by means of a methodology based on broken-symmetry unrestricted density functional theory. These novel and highly unstable compounds present superexchange interactions between two Mn centers, each one with S = 5/2 through anionic "guests" such as oxygen, benzene, or hydrides or through the cationic ring formed by amide ligands and alkali metals (Na, Li). Magnetic exchange couplings calculated at B3LYP/6-31G(d,p) level yield strong antiferromagnetic couplings for compounds linked via an oxygen atom or hydride and very small antiferromagnetic couplings for those linked via a benzene molecule, deprotonated in either 1,4- or 1,3- positions. Analysis of the magnetic orbitals and spin polarization maps provide an understanding of the exchange mechanism between the Mn centers. The dependence of J with respect to 10 different density functional theory potentials employed and the basis set has been analyzed.
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Affiliation(s)
- Ederley Vélez
- Departament de Química Física i Analítica, Universitat Jaume I, 12071, Castelló, Spain
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Li SF, Shao Z, Han S, Xue X, Wang F, Sun Q, Jia Y, Guo ZX. Role of Ag-doping in small transition metal clusters from first-principles simulations. J Chem Phys 2009; 131:184301. [DOI: 10.1063/1.3261728] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
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23
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Tzeli D, Miranda U, Kaplan IG, Mavridis A. First principles study of the electronic structure and bonding of Mn2. J Chem Phys 2008; 129:154310. [DOI: 10.1063/1.2993750] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023] Open
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