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Alcoba DR, Oña OB, Torre A, Lain L, Sierra G, Massaccesi GE. A variance-based optimization for determining ground and excited N-electron wave functions within the doubly occupied configuration interaction scheme. J Chem Phys 2024; 160:164107. [PMID: 38656446 DOI: 10.1063/5.0191857] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2023] [Accepted: 04/07/2024] [Indexed: 04/26/2024] Open
Abstract
This work describes optimizations of N-electron system wave functions by means of the simulated annealing technique within the doubly occupied configuration interaction framework. Using that technique, we minimize the energy variance of a Hamiltonian, providing determinations of wave functions corresponding to ground or excited states in an identical manner. The procedure that allows us to determine electronic spectra can be performed using treatments of restricted or unrestricted types. The results found in selected systems, described in terms of energy, spin, and wave function, are analyzed, showing the performance of each method. We also compare these results with those arising from more traditional approaches that minimize the energy, in both restricted and unrestricted versions, and with those obtained from the full configuration interaction treatment.
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Affiliation(s)
- Diego R Alcoba
- Universidad de Buenos Aires, Facultad de Ciencias Exactas y Naturales, Departamento de Física, Ciudad Universitaria, 1428 Buenos Aires, Argentina
- CONICET - Universidad de Buenos Aires, Instituto de Física de Buenos Aires (IFIBA), Ciudad Universitaria, 1428 Buenos Aires, Argentina
| | - Ofelia B Oña
- Instituto de Investigaciones Fisicoquímicas Teóricas y Aplicadas, Universidad Nacional de La Plata, Consejo Nacional de Investigaciones Cientıficas y Tócnicas, Diag. 113 y 64 (S/N), Sucursal 4, CC 16, 1900 La Plata, Argentina
| | - Alicia Torre
- Departamento de Química Física, Facultad de Ciencia y Tecnología, Universidad del País Vasco, Apdo. 644, E-48080 Bilbao, Spain
| | - Luis Lain
- Departamento de Química Física, Facultad de Ciencia y Tecnología, Universidad del País Vasco, Apdo. 644, E-48080 Bilbao, Spain
| | - Guadalupe Sierra
- Universidad de Buenos Aires, Facultad de Ciencias Exactas y Naturales, Departamento de Física, Ciudad Universitaria, 1428 Buenos Aires, Argentina
| | - Gustavo E Massaccesi
- Departamento de Ciencias Exactas, Ciclo Básico Común, Universidad de Buenos Aires, Ciudad Universitaria, 1428 Buenos Aires, Argentina
- Instituto de Investigaciones Matemáticas Luis Santaló, Consejo Nacional de Investigaciones Científicas y Técnicas, Universidad de Buenos Aires, Ciudad Universitaria, 1428 Buenos Aires, Argentina
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Nakatani K, Higashi M, Sato H. Extraction of local spin-coupled states by second quantized operators. J Chem Phys 2022; 157:014112. [PMID: 35803792 DOI: 10.1063/5.0092834] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
We present a methodology for analyzing chemical bonds embedded in the electronic wave function of molecules, especially in terms of spin correlations or so-called "local spin." In this paper, based on biorthogonal second quantization, the spin correlation functions of molecules are naturally introduced, which enables us to extract local singlet and local triplet elements from the wave function. We also clarify the relationship between these spin correlations and traditional chemical concepts, i.e., resonance structures. Several chemical reactions, including the intramolecular radical cyclization and the formation of preoxetane, are demonstrated to verify the analysis method numerically.
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Affiliation(s)
- Kaho Nakatani
- Department of Molecular Engineering, Graduate School of Engineering, Kyoto University, Kyoto 615-8510, Japan
| | - Masahiro Higashi
- Department of Molecular Engineering, Graduate School of Engineering, Kyoto University, Kyoto 615-8510, Japan
| | - Hirofumi Sato
- Department of Molecular Engineering, Graduate School of Engineering, Kyoto University, Kyoto 615-8510, Japan
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Ríos E, Alcoba DR, Lain L, Torre A, Oña OB, Massaccesi GE. Variational determination of the two-electron reduced density matrix within the doubly occupied configuration interaction framework: Treatments of triplet N-electron systems. J Chem Phys 2022; 157:014102. [DOI: 10.1063/5.0088125] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
This work performs variational determinations of two-electron reduced density matrices corresponding to open-shell N-electron systems within the framework of the doubly occupied configuration interaction treatment, traditionally limited to studies of closed-shell systems. The procedure has allowed us to describe satisfactorily molecular systems in triplet states following two methods. One of them adds hydrogen atoms at an infinite distance of the triplet system studied, constituting a singlet supersystem. Energies and reduced density matrices of the triplet system are obtained by removing the contributions of the added atoms from the singlet supersystem results. The second procedure determines variationally the two-electron reduced density matrices corresponding to the triplet systems by means of adequate couplings of basis-set functions. Both models have been managed by imposing N-representability conditions on the reduced density matrix calculations. Results obtained from these methods for molecular systems in triplet ground states are reported and compared with those provided by benchmark methods.
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Affiliation(s)
| | - Diego Ricardo Alcoba
- Departmento de Fisica, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Argentina
| | - Luis Lain
- Quimica Fisica, Universidad del Pais Vasco Facultad de Ciencia y Tecnologia, Spain
| | - Alicia Torre
- Quimica Fisica, Universidad del Pais Vasco, Spain
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Nakatani K, Higashi M, Fukuda R, Sato H. An analysis of valence electronic structure from a viewpoint of resonance theory: Tautomerization of formamide and diazadiboretidine. J Comput Chem 2021; 42:1662-1669. [PMID: 34114237 DOI: 10.1002/jcc.26703] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2021] [Revised: 05/03/2021] [Accepted: 05/27/2021] [Indexed: 01/08/2023]
Abstract
The resonance theory is still very useful in understanding the valence electron structure. However, such a viewpoint is not usually obtained by general-purpose quantum chemical calculations, instead requires rather special treatment such as valence bond methods. In this study, we propose a method based on second quantization to analyze the results obtained by general-purpose quantum chemical calculations from the local point of view of electronic structure and analyze diazadiboretidine and the tautomerization of formamide. This method requires only the "PS"-matrix, consisting of the density matrix (P-matrix) and overlap matrix, and can be computed with a comparable load to that of Mulliken population analysis. A key feature of the method is that, unlike other methods proposed so far, it makes direct use of the results of general-purpose quantum chemical calculations.
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Affiliation(s)
- Kaho Nakatani
- Department of Molecular Engineering, Kyoto University, Kyoto, Japan
| | - Masahiro Higashi
- Department of Molecular Engineering, Kyoto University, Kyoto, Japan.,Center for the Promotion of Interdisciplinary Education and Research, Elements Strategy Initiative for Catalysts and Batteries (ESICB), Kyoto University, Kyoto, Japan
| | - Ryoichi Fukuda
- Center for the Promotion of Interdisciplinary Education and Research, Elements Strategy Initiative for Catalysts and Batteries (ESICB), Kyoto University, Kyoto, Japan
| | - Hirofumi Sato
- Department of Molecular Engineering, Kyoto University, Kyoto, Japan.,Center for the Promotion of Interdisciplinary Education and Research, Elements Strategy Initiative for Catalysts and Batteries (ESICB), Kyoto University, Kyoto, Japan.,Fukui Institute for Fundamental Chemistry, Kyoto University, Kyoto, Japan
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Affiliation(s)
- Frank Weinhold
- Theoretical Chemistry and Department of Chemistry University of Wisconsin Madison Wisconsin 53706 USA
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Ravaei I, Azami SM. Block deformation analysis: Density matrix blocks as intramolecular deformation density. J Comput Chem 2020; 41:2446-2458. [PMID: 32844467 DOI: 10.1002/jcc.26400] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2020] [Revised: 07/04/2020] [Accepted: 07/28/2020] [Indexed: 11/07/2022]
Abstract
Block deformation analysis as deformation density of atomic orbitals is introduced to analyze intramolecular interactions. In this respect, density matrix blocks in terms of natural atomic orbitals are employed to find interacting and noninteracting multicenter subsystem and extract the corresponding deformation density. Eigenanalysis of this deformation density is performed to result eigenvalues and eigenorbitals as displaced charge due to the intramolecular interaction and orbital space responsible for charge reorganization, respectively, that possesses advantages of other methods, simultaneously. It is applied to several small molecules, different types of carbon allotropes including zero-, one-, and two-dimensional nanostructures, and challenging systems such as ortho-hydrogen atoms in planar biphenyl. Results highly correlate with delocalization and Wiberg bond indices and show that eigenvalues of block deformation analysis deserved to be considered as bonding index.
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Affiliation(s)
- Isa Ravaei
- Chemistry Department, College of Sciences, Yasouj University, Yasouj, Iran
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Alcoba DR, Torre A, Lain L, Massaccesi GE, Oña OB, Ríos E. Unrestricted treatment for the direct variational determination of the two-electron reduced density matrix for doubly occupied-configuration-interaction wave functions. J Chem Phys 2019; 150:164106. [PMID: 31042927 DOI: 10.1063/1.5092182] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
This work extends to the unrestricted orbital approach the procedure described in our previous report [Alcoba et al., J. Chem. Phys. 148, 024105 (2018)] for determining variationally the two-electron reduced density matrix arising from doubly occupied-configuration-interaction wave functions by imposing two- and three-index N-representability conditions. An analysis of the numerical results obtained in selected systems, from both restricted and unrestricted treatments, allows one to assess the performance of these methodologies as well as to show the influence of the P, Q, G, T1, and T2 positivity conditions. We highlight the satisfactory results obtained within the unrestricted scheme.
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Affiliation(s)
- Diego R Alcoba
- Departamento de Física, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires and Instituto de Física de Buenos Aires, Consejo Nacional de Investigaciones Científicas y Técnicas. Ciudad Universitaria, 1428 Buenos Aires, Argentina
| | - Alicia Torre
- Departamento de Química Física, Facultad de Ciencia y Tecnología, Universidad del País Vasco. Apdo. 644, E-48080 Bilbao, Spain
| | - Luis Lain
- Departamento de Química Física, Facultad de Ciencia y Tecnología, Universidad del País Vasco. Apdo. 644, E-48080 Bilbao, Spain
| | - Gustavo E Massaccesi
- Departamento de Ciencias Exactas, Ciclo Básico Común, Universidad de Buenos Aires. Ciudad Universitaria, 1428 Buenos Aires, Argentina
| | - Ofelia B Oña
- Instituto de Investigaciones Fisicoquímicas Teóricas y Aplicadas, Universidad Nacional de La Plata, CCT La Plata, Consejo Nacional de Investigaciones Científicas y Técnicas. Diag. 113 y 64 (S/N), Sucursal 4, CC 16, 1900 La Plata, Argentina
| | - Elías Ríos
- Instituto de Investigaciones Fisicoquímicas Teóricas y Aplicadas, Universidad Nacional de La Plata, CCT La Plata, Consejo Nacional de Investigaciones Científicas y Técnicas. Diag. 113 y 64 (S/N), Sucursal 4, CC 16, 1900 La Plata, Argentina
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Kyriakidou K, Karafiloglou P, Glendening E, Weinhold F. To Be or Not to Be: Demystifying the 2nd‐Quantized Picture of Complex Electronic Configuration Patterns in Chemistry with Natural Poly‐Electron Population Analysis. J Comput Chem 2019; 40:1509-1520. [DOI: 10.1002/jcc.25803] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2018] [Revised: 01/23/2019] [Accepted: 02/03/2019] [Indexed: 11/09/2022]
Affiliation(s)
| | | | - Eric Glendening
- Department of Chemistry and Physics Indiana State University Terre Haute Indiana, 47809
| | - Frank Weinhold
- Theoretical Chemistry Institute and Department of Chemistry University of Wisconsin‐Madison Madison Wisconsin, 53706
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Glendening ED, Weinhold F. Efficient evaluation of poly-electron populations in natural bond orbital analysis. Chem Phys Lett 2018. [DOI: 10.1016/j.cplett.2018.09.013] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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Alcoba DR, Torre A, Lain L, Massaccesi GE, Oña OB, Honoré EM, Poelmans W, Van Neck D, Bultinck P, De Baerdemacker S. Direct variational determination of the two-electron reduced density matrix for doubly occupied-configuration-interaction wave functions: The influence of three-index N-representability conditions. J Chem Phys 2018; 148:024105. [PMID: 29331147 DOI: 10.1063/1.5008811] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
This work proposes the variational determination of two-electron reduced density matrices corresponding to the ground state of N-electron systems within the doubly occupied-configuration-interaction methodology. The P, Q, and G two-index N-representability conditions have been extended to the T1 and T2 (T2') three-index ones and the resulting optimization problem has been addressed using a standard semidefinite program. We report results obtained from the doubly occupied-configuration-interaction method, from the two-index constraint variational procedure and from the two- and three-index constraint variational treatment. The discussion of these results along with a study of the computational cost demanded shows the usefulness of our proposal.
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Affiliation(s)
- Diego R Alcoba
- Departamento de Física, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Ciudad Universitaria, 1428 Buenos Aires, Argentina
| | - Alicia Torre
- Departamento de Química Física, Facultad de Ciencia y Tecnología, Universidad del País Vasco. Apdo. 644, E-48080 Bilbao, Spain
| | - Luis Lain
- Departamento de Química Física, Facultad de Ciencia y Tecnología, Universidad del País Vasco. Apdo. 644, E-48080 Bilbao, Spain
| | - Gustavo E Massaccesi
- Departamento de Ciencias Exactas, Ciclo Básico Común, Universidad de Buenos Aires, Ciudad Universitaria, 1428 Buenos Aires, Argentina
| | - Ofelia B Oña
- Instituto de Investigaciones Fisicoquímicas Teóricas y Aplicadas, Universidad Nacional de La Plata, CCT La Plata, Consejo Nacional de Investigaciones Científicas y Técnicas. Diag. 113 y 64 (S/N), Sucursal 4, CC 16, 1900 La Plata, Argentina
| | - Eduardo M Honoré
- Departamento de Física, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Ciudad Universitaria, 1428 Buenos Aires, Argentina
| | - Ward Poelmans
- Center for Molecular Modeling, Ghent University, Technologiepark 903, B-9052 Zwijnaarde, Belgium
| | - Dimitri Van Neck
- Center for Molecular Modeling, Ghent University, Technologiepark 903, B-9052 Zwijnaarde, Belgium
| | - Patrick Bultinck
- Department of Inorganic and Physical Chemistry, Ghent University, Krijgslaan 281 (S3), 9000 Gent, Belgium
| | - Stijn De Baerdemacker
- Center for Molecular Modeling, Ghent University, Technologiepark 903, B-9052 Zwijnaarde, Belgium
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Hybrid Treatments Based on Determinant Seniority Numbers and Spatial Excitation Levels in the Configuration Interaction Framework. ADVANCES IN QUANTUM CHEMISTRY 2018. [DOI: 10.1016/bs.aiq.2017.05.003] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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Kyriakidou K, Karafiloglou P. Natural bond orbitals: Local sets showing minimal intra-pair correlations and minimal unpaired electron populations. COMPUT THEOR CHEM 2017. [DOI: 10.1016/j.comptc.2016.11.017] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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13
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Rincón L, Mora JR, Torres FJ, Almeida R. On the activation of σ-bonds by electric fields: A Valence Bond perspective. Chem Phys 2016. [DOI: 10.1016/j.chemphys.2016.08.008] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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Alcoba DR, Torre A, Lain L, Massaccesi GE, Oña OB, Capuzzi P. Spin contamination-free N-electron wave functions in the excitation-based configuration interaction treatment. J Chem Phys 2016; 145:014109. [PMID: 27394101 DOI: 10.1063/1.4955159] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
This work deals with the spin contamination in N-electron wave functions provided by the excitation-based configuration interaction methods. We propose a procedure to ensure a suitable selection of excited N-electron Slater determinants with respect to a given reference determinant, required in these schemes. The procedure guarantees the construction of N-electron wave functions which are eigenfunctions of the spin-squared operator Sˆ(2), avoiding any spin contamination. Our treatment is based on the evaluation of the excitation level of the determinants by means of the expectation value of an excitation operator formulated in terms of spin-free replacement operators. We report numerical determinations of energies and 〈Sˆ(2)〉 expectation values, arising from our proposal as well as from traditional configuration interaction methods, in selected open-shell systems, in order to compare the behavior of these procedures and their computational costs.
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Affiliation(s)
- Diego R Alcoba
- Departamento de Física, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires and Instituto de Física de Buenos Aires, Consejo Nacional de Investigaciones Científicas y Técnicas, Ciudad Universitaria, 1428 Buenos Aires, Argentina
| | - Alicia Torre
- Departamento de Química Física, Facultad de Ciencia y Tecnología, Universidad del País Vasco, Apdo. 644 E-48080 Bilbao, Spain
| | - Luis Lain
- Departamento de Química Física, Facultad de Ciencia y Tecnología, Universidad del País Vasco, Apdo. 644 E-48080 Bilbao, Spain
| | - Gustavo E Massaccesi
- Departamento de Ciencias Exactas, Ciclo Básico Común, Universidad de Buenos Aires, Ciudad Universitaria, 1428 Buenos Aires, Argentina
| | - Ofelia B Oña
- Instituto de Investigaciones Fisicoquímicas Teóricas y Aplicadas, Universidad Nacional de La Plata, CCT La Plata, Consejo Nacional de Investigaciones Científicas y Técnicas, Diag. 113 y 64 (S/N), Sucursal 4, CC 16, 1900 La Plata, Argentina
| | - Pablo Capuzzi
- Departamento de Física, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires and Instituto de Física de Buenos Aires, Consejo Nacional de Investigaciones Científicas y Técnicas, Ciudad Universitaria, 1428 Buenos Aires, Argentina
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Alcoba DR, Torre A, Lain L, Massaccesi GE, Oña OB, Ayers PW, Van Raemdonck M, Bultinck P, Van Neck D. Performance of Shannon-entropy compacted N-electron wave functions for configuration interaction methods. Theor Chem Acc 2016. [DOI: 10.1007/s00214-016-1905-x] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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Papadopoulos AG, Charistos ND, Kyriakidou K, Sigalas MP. Study of Electron Delocalization in 1,2-, 1,3-, and 1,4-Azaborines Based on the Canonical Molecular Orbital Contributions to the Induced Magnetic Field and Polyelectron Population Analysis. J Phys Chem A 2015; 119:10091-100. [PMID: 26348255 DOI: 10.1021/acs.jpca.5b06027] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The electron delocalization in 1,2-azaborine, 1,3-azaborine, and 1,4-azaborine is studied using canonical molecular orbital contributions to the induced magnetic field (CMO-IMF) method and polyelectron population analysis (PEPA). Contour maps of the out-of-plane component of the induced magnetic field (Bz(ind)) of the π system show that the three azaborines, in contrast with borazine, sustain much of benzene's π-aromatic character. Among them, 1,3-azaborine exhibits the strongest π delocalization, while 1,4-azaborine is the weakest. Contour maps of Bz(ind) for individual π orbitals reveal that the differentiation of the magnetic response among the three isomers originates from the π-HOMO orbitals, whose magnetic response is governed by rotational allowed transitions to unoccupied orbitals. The low symmetry of azaborines enables a paratropic response from HOMO to unoccupied orbitals excitations, with their magnitude depending on the shape of interacting orbitals. 1,3-Azaborine presents negligible paratropic contributions to Bz(ind) from HOMO to unoccupied orbitals transitions, where 1,2- and 1,4-azaborine present substantial paratropic contributions, which lead to reduced diatropic response. Natural bond orbital (NBO) analysis employing PEPA shows that only the 1,3-azaborine contains π-electron fully delocalized resonance structures.
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Affiliation(s)
- Anastasios G Papadopoulos
- Aristotle University of Thessaloniki , Department of Chemistry, Laboratory of Applied Quantum Chemistry, Thessaloniki 54124, Greece
| | - Nickolas D Charistos
- Aristotle University of Thessaloniki , Department of Chemistry, Laboratory of Applied Quantum Chemistry, Thessaloniki 54124, Greece
| | - Katerina Kyriakidou
- Aristotle University of Thessaloniki , Department of Chemistry, Laboratory of Applied Quantum Chemistry, Thessaloniki 54124, Greece
| | - Michael P Sigalas
- Aristotle University of Thessaloniki , Department of Chemistry, Laboratory of Applied Quantum Chemistry, Thessaloniki 54124, Greece
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Alcoba DR, Oña OB, Massaccesi GE, Torre A, Lain L, Notario R, Oliva JM. Molecular magnetism incloso-azadodecaborane supericosahedrons. Mol Phys 2015. [DOI: 10.1080/00268976.2015.1076900] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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Alcoba DR, Torre A, Lain L, Oña OB, Capuzzi P, Van Raemdonck M, Bultinck P, Van Neck D. A hybrid configuration interaction treatment based on seniority number and excitation schemes. J Chem Phys 2014; 141:244118. [DOI: 10.1063/1.4904755] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- Diego R. Alcoba
- Departamento de Física, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires and Instituto de Física de Buenos Aires, Consejo Nacional de Investigaciones Científicas y Técnicas, Ciudad Universitaria, 1428 Buenos Aires, Argentina
| | - Alicia Torre
- Departamento de Química Física, Facultad de Ciencia y Tecnología, Universidad del País Vasco, Apdo. 644 E-48080 Bilbao, Spain
| | - Luis Lain
- Departamento de Química Física, Facultad de Ciencia y Tecnología, Universidad del País Vasco, Apdo. 644 E-48080 Bilbao, Spain
| | - Ofelia B. Oña
- Instituto de Investigaciones Fisicoquímicas Teóricas y Aplicadas, Universidad Nacional de La Plata, CCT La Plata, Consejo Nacional de Investigaciones Científicas y Técnicas, Diag. 113 y 64 (S/N), Sucursal 4, CC 16, 1900 La Plata, Argentina
| | - Pablo Capuzzi
- Departamento de Física, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires and Instituto de Física de Buenos Aires, Consejo Nacional de Investigaciones Científicas y Técnicas, Ciudad Universitaria, 1428 Buenos Aires, Argentina
| | - Mario Van Raemdonck
- Department of Inorganic and Physical Chemistry, Ghent University, Krijgslaan 281 (S3), 9000 Gent, Belgium
| | - Patrick Bultinck
- Department of Inorganic and Physical Chemistry, Ghent University, Krijgslaan 281 (S3), 9000 Gent, Belgium
| | - Dimitri Van Neck
- Center for Molecular Modelling, Ghent University, Technologiepark 903, 9052 Zwijnaarde, Belgium
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Alcoba DR, Torre A, Lain L, Massaccesi GE, Oña OB. Configuration interaction wave functions: A seniority number approach. J Chem Phys 2014; 140:234103. [DOI: 10.1063/1.4882881] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
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Alcoba DR, Torre A, Lain L, Massaccesi GE, Oña OB. Seniority number in spin-adapted spaces and compactness of configuration interaction wave functions. J Chem Phys 2013; 139:084103. [DOI: 10.1063/1.4818755] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Alcoba DR, Torre A, Lain L, Bochicchio RC. Determination of Local Spins by Means of a Spin-Free Treatment. J Chem Theory Comput 2011; 7:3560-6. [DOI: 10.1021/ct200594f] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Diego R. Alcoba
- Departamento de Física, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires and Instituto de Física de Buenos Aires, Consejo Nacional de Investigaciones Científicas y Técnicas, Ciudad Universitaria, 1428, Buenos Aires, Argentina
| | - Alicia Torre
- Departamento de Química Física, Facultad de Ciencia y Tecnología, Universidad del País Vasco, Apdo. 644 E-48080 Bilbao, Spain
| | - Luis Lain
- Departamento de Química Física, Facultad de Ciencia y Tecnología, Universidad del País Vasco, Apdo. 644 E-48080 Bilbao, Spain
| | - Roberto C. Bochicchio
- Departamento de Física, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires and Instituto de Física de Buenos Aires, Consejo Nacional de Investigaciones Científicas y Técnicas, Ciudad Universitaria, 1428, Buenos Aires, Argentina
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Ikeda A, Nakao Y, Sato H, Sakaki S. A resonance theory consistent with Mulliken-population concept. Chem Phys Lett 2011. [DOI: 10.1016/j.cplett.2011.02.033] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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Nishida S, Kariyazono K, Yamanaka A, Fukui K, Sato K, Takui T, Nakasuji K, Morita Y. Electronic Stabilization Effect of a Spin‐Delocalized Neutral Radical: Synthesis of an 8‐Cyano‐6‐oxophenalenoxyl Derivative and Quantitative Evaluation of the Electronic Spin Structure in terms of Resonance Structures. Chem Asian J 2011; 6:1188-96. [DOI: 10.1002/asia.201000793] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2010] [Indexed: 11/07/2022]
Affiliation(s)
- Shinsuke Nishida
- Department of Chemistry, Graduate School of Science, Osaka University, Toyonaka, Osaka 560‐0043 (Japan), Fax: (+81) 6‐6850‐5395
- Department of Chemistry, Graduate School of Science, Osaka City University, Sumiyoshi‐ku, Osaka 558‐8585 (Japan), Fax: (+81) 6‐6605‐2522
| | - Kazuki Kariyazono
- Department of Chemistry, Graduate School of Science, Osaka University, Toyonaka, Osaka 560‐0043 (Japan), Fax: (+81) 6‐6850‐5395
| | - Azusa Yamanaka
- Department of Chemistry, Graduate School of Science, Osaka University, Toyonaka, Osaka 560‐0043 (Japan), Fax: (+81) 6‐6850‐5395
| | - Kozo Fukui
- Department of Chemistry, Graduate School of Science, Osaka University, Toyonaka, Osaka 560‐0043 (Japan), Fax: (+81) 6‐6850‐5395
| | - Kazunobu Sato
- Department of Chemistry, Graduate School of Science, Osaka City University, Sumiyoshi‐ku, Osaka 558‐8585 (Japan), Fax: (+81) 6‐6605‐2522
| | - Takeji Takui
- Department of Chemistry, Graduate School of Science, Osaka City University, Sumiyoshi‐ku, Osaka 558‐8585 (Japan), Fax: (+81) 6‐6605‐2522
| | - Kazuhiro Nakasuji
- Department of Chemistry, Graduate School of Science, Osaka University, Toyonaka, Osaka 560‐0043 (Japan), Fax: (+81) 6‐6850‐5395
| | - Yasushi Morita
- Department of Chemistry, Graduate School of Science, Osaka University, Toyonaka, Osaka 560‐0043 (Japan), Fax: (+81) 6‐6850‐5395
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Investigating sigma bonds in an electric field from the Pauling’s perspective: the behavior of Cl–X and H–X (X = C, Si) bonds. Theor Chem Acc 2009. [DOI: 10.1007/s00214-009-0650-9] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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