1
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Hosseini S, Ketabi S, Hasheminasab G. QSAR study of antituberculosis activity of oxadiazole derivatives using DFT calculations. J Recept Signal Transduct Res 2022; 42:503-511. [PMID: 35263550 DOI: 10.1080/10799893.2022.2044860] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
Mycobacterium tuberculosis (Mtb) is the causative agent of infectious diseases worldwide. Oxadiazole derivatives have many biological activities and can be a good alternative to antimicrobial drugs. In this study, the quantitative structure-activity relationship (QSAR) of fifty-one novel oxadiazoles derivatives has been studied using the density functional theory (DFT) and statistical methods. Becke's three-parameter hybrid method and the Lee-Yang-Parr B3LYP functional employing 6-31++G (d) basis set are used to calculated quantum chemical descriptors using Gaussian09 software. The other descriptors including Lipinski, physicochemistry, topological, etc. were calculated using Chembio3d software. Statistically, the best correlation between the independent variables and the PMIC as the dependent variable was a 6-variable equation for which the correlation coefficient were as follows R2 = 0.86 and R = 0.93. Also, the values of MAE = 0.003 and Q2CV = 0.9 confirm the acceptability of the obtained model. The obtained equation shows that NRB, energy gap (ΔE), Henry's law constant, O-C, and C-N bonds length, and the Free Gibbs energy have the highest correlation with the anti-Tb activity.
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Affiliation(s)
- Sharieh Hosseini
- Department of Chemistry, Faculty of Pharmaceutical Chemistry, Tehran Medical Sciences, Islamic Azad University, Tehran, Iran
| | - Sepideh Ketabi
- Department of Chemistry, Faculty of Pharmaceutical Chemistry, Tehran Medical Sciences, Islamic Azad University, Tehran, Iran
| | - Golnar Hasheminasab
- School of Pharmacy, Shahid Beheshti University of Medical Sciences, Tehran, Iran
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2
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Xu Z, Zhao J, Zhao D, Yang Z. Theoretical Investigation on Regioselectivities of
Diels‐Alder
Reactions by Conjugated Effect. CHINESE J CHEM 2020. [DOI: 10.1002/cjoc.202000285] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Affiliation(s)
- Zhen‐Zhen Xu
- Jiangxi Province Key Laboratory of the Causes and Control of Atmospheric Pollution and School of Chemistry, Biology and Materials Science, East China University of Technology Nanchang Jiangxi 330013 China
| | - Jian Zhao
- School of Chemistry and Chemical Engineering, Liaoning Normal University Dalian Liaoning 116029 China
| | - Dong‐Xia Zhao
- School of Chemistry and Chemical Engineering, Liaoning Normal University Dalian Liaoning 116029 China
| | - Zhong‐Zhi Yang
- School of Chemistry and Chemical Engineering, Liaoning Normal University Dalian Liaoning 116029 China
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3
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Bettens T, Alonso M, De Proft F, Hamlin TA, Bickelhaupt FM. Ambident Nucleophilic Substitution: Understanding Non-HSAB Behavior through Activation Strain and Conceptual DFT Analyses. Chemistry 2020; 26:3884-3893. [PMID: 31957943 PMCID: PMC7154642 DOI: 10.1002/chem.202000272] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2020] [Indexed: 01/31/2023]
Abstract
The ability to understand and predict ambident reactivity is key to the rational design of organic syntheses. An approach to understand trends in ambident reactivity is the hard and soft acids and bases (HSAB) principle. The recent controversy over the general validity of this principle prompted us to investigate the competing gas-phase SN 2 reaction channels of archetypal ambident nucleophiles CN- , OCN- , and SCN- with CH3 Cl (SN 2@C) and SiH3 Cl (SN 2@Si), using DFT calculations. Our combined analyses highlight the inability of the HSAB principle to correctly predict the reactivity trends of these simple, model reactions. Instead, we have successfully traced reactivity trends to the canonical orbital-interaction mechanism and the resulting nucleophile-substrate interaction energy. The HOMO-LUMO orbital interactions set the trend in both SN 2@C and SN 2@Si reactions. We provide simple rules for predicting the ambident reactivity of nucleophiles based on our Kohn-Sham molecular orbital analysis.
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Affiliation(s)
- Tom Bettens
- Eenheid Algemene Chemie (ALGC)Vrije Universiteit BrusselPleinlaan 21050BrusselsBelgium
| | - Mercedes Alonso
- Eenheid Algemene Chemie (ALGC)Vrije Universiteit BrusselPleinlaan 21050BrusselsBelgium
| | - Frank De Proft
- Eenheid Algemene Chemie (ALGC)Vrije Universiteit BrusselPleinlaan 21050BrusselsBelgium
| | - Trevor A. Hamlin
- Department of Theoretical ChemistryAmsterdam Institute of Molecular and Life Sciences (AIMMS)Amsterdam Center for Multiscale Modeling (ACMM)Vrije Universiteit AmsterdamDe Boelelaan 10831081HVAmsterdamThe Netherlands
| | - F. Matthias Bickelhaupt
- Department of Theoretical ChemistryAmsterdam Institute of Molecular and Life Sciences (AIMMS)Amsterdam Center for Multiscale Modeling (ACMM)Vrije Universiteit AmsterdamDe Boelelaan 10831081HVAmsterdamThe Netherlands
- Institute for Molecules and Materials (IMM)Radboud University NijmegenHeyendaalseweg 1356525AJNijmegenThe Netherlands
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4
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Carmona-Espíndola J, Gázquez JL, Vela A, Trickey SB. Negative Electron Affinities and Derivative Discontinuity Contribution from a Generalized Gradient Approximation Exchange Functional. J Phys Chem A 2020; 124:1334-1342. [PMID: 31978298 DOI: 10.1021/acs.jpca.9b10956] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
Two methods to calculate negative electron affinities systematically from ground-state density functional methods are presented. One makes use of the lowest unoccupied molecular orbital energy shift provided by approximate inclusion of derivative discontinuity in the nearly correct asymptotic potential (NCAP) nonempirical, constraint-based generalized gradient approximation exchange functional. The other uses a second-order perturbation calculation of the derivative discontinuity based on the NCAP exchange-correlation potential. On a set of thirty-eight molecules, NCAP leads to a rather accurate description that is improved further through the perturbation correction. The results presented show the importance of the asymptotic behavior of the exchange-correlation potential in the calculation of negative electron affinities as well as demonstrating the versatility of the NCAP functional.
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Affiliation(s)
- Javier Carmona-Espíndola
- Departamento de Química , CONACYT-Universidad Autónoma Metropolitana-Iztapalapa , Av. San Rafael Atlixco 186 , Ciudad de México , 09340 , México
| | - José L Gázquez
- Departamento de Química , Universidad Autónoma Metropolitana-Iztapalapa , Av. San Rafael Atlixco 186 , México, Ciudad de México , 09340 , México
| | - Alberto Vela
- Departamento de Química , Centro de Investigación y de Estudios Avanzados , Av. Instituto Politécnico Nacional 2508 , Ciudad de México , 07360 , México
| | - S B Trickey
- Quantum Theory Project, Department of Physics and Department of Chemistry , P.O. Box 118435, University of Florida , Gainesville , Florida 32611-8435 , United States
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5
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Oller J, Saez DA, Vöhringer-Martinez E. Atom-Condensed Fukui Function in Condensed Phases and Biological Systems and Its Application to Enzymatic Fixation of Carbon Dioxide. J Phys Chem A 2020; 124:849-857. [PMID: 31951411 DOI: 10.1021/acs.jpca.9b07012] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Local reactivity descriptors such as atom-condensed Fukui functions are promising computational tools to study chemical reactivity at specific sites within a molecule. Their applications have been mainly focused on isolated molecules in their most stable conformation without considering the effects of the surroundings. Here we propose to combine quantum mechanics/molecular mechanics Born-Oppenheimer molecular dynamics simulations to obtain the microstates (configurations) of a molecular system using different representations of the molecular environment and calculate Boltzmann-weighted atom-condensed local reactivity descriptors based on conceptual density functional theory. Our approach takes the conformational fluctuations of the molecular system and the polarization of its electron density by the environment into account, allowing us to analyze the effect of the molecular environment on reactivity. In this contribution, we apply the method mentioned above to the catalytic fixation of carbon dioxide by crotonyl-CoA carboxylase/reductase and study if the enzyme alters the reactivity of its substrate compared with an aqueous solution. Our main result is that the protein environment activates the substrate by the elimination of solute-solvent hydrogen bonds from aqueous solution in the two elementary steps of the reaction mechanism: the nucleophilic attack of a hydride anion from NADPH on the α,β-unsaturated thioester and the electrophilic attack of carbon dioxide on the formed enolate species.
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Affiliation(s)
- Javier Oller
- Departamento de Fı́sico-Quı́mica, Facultad de Ciencias Quı́micas , Universidad de Concepción , Concepción 4070386 , Chile
| | - David Adrian Saez
- Departamento de Fı́sico-Quı́mica, Facultad de Ciencias Quı́micas , Universidad de Concepción , Concepción 4070386 , Chile
| | - Esteban Vöhringer-Martinez
- Departamento de Fı́sico-Quı́mica, Facultad de Ciencias Quı́micas , Universidad de Concepción , Concepción 4070386 , Chile
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6
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Molecular Structure, Spectroscopic (FT-IR, FT-Raman, 13C and 1H NMR) Analysis, HOMO-LUMO Energies, Mulliken, MEP and Thermal Properties of New Chalcone Derivative by DFT Calculation. ACTA ACUST UNITED AC 2019. [DOI: 10.1016/j.matpr.2019.02.078] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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7
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Geboes Y, De Vleeschouwer F, De Proft F, Herrebout WA. Exploiting the σ-Hole Concept: An Infrared and Raman-Based Characterization of the S⋅⋅⋅O Chalcogen Bond between 2,2,4,4-Tetrafluoro-1,3-dithiethane and Dimethyl Ether. Chemistry 2017; 23:17384-17392. [DOI: 10.1002/chem.201704406] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2017] [Indexed: 12/18/2022]
Affiliation(s)
- Yannick Geboes
- Department of Chemistry; University of Antwerp, Groenenborgerlaan 171, 2020 Antwerp (Belgium), Eenheid Algemene Chemie (ALGC), Member of the QCMM VUB-UGent Alliance Research Group, Vrije Universiteit Brussel (VUB); Pleinlaan 2 1050 Brussels Belgium
| | - Freija De Vleeschouwer
- Eenheid Algemene Chemie (ALGC), Member of the QCMM VUB-UGent Alliance Research Group; Vrije Universiteit Brussel (VUB); Pleinlaan 2 1050 Brussels Belgium
| | - Frank De Proft
- Eenheid Algemene Chemie (ALGC), Member of the QCMM VUB-UGent Alliance Research Group; Vrije Universiteit Brussel (VUB); Pleinlaan 2 1050 Brussels Belgium
| | - Wouter A. Herrebout
- Department of Chemistry; University of Antwerp; Groenenborgerlaan 171 2020 Antwerp Belgium
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8
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Teale AM, De Proft F, Geerlings P, Tozer DJ. Atomic electron affinities and the role of symmetry between electron addition and subtraction in a corrected Koopmans approach. Phys Chem Chem Phys 2015; 16:14420-34. [PMID: 24406854 DOI: 10.1039/c3cp54528h] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
The essential aspects of zero-temperature grand-canonical ensemble density-functional theory are reviewed in the context of spin-density-functional theory and are used to highlight the assumption of symmetry between electron addition and subtraction that underlies the corrected Koopmans approach of Tozer and De Proft (TDP) for computing electron affinities. The issue of symmetry is then investigated in a systematic study of atomic electron affinities, comparing TDP affinities with those from a conventional Koopmans evaluation and electronic energy differences. Although it cannot compete with affinities determined from energy differences, the TDP expression yields results that are a significant improvement over those from the conventional Koopmans expression. Key insight into the results from both expressions is provided by an analysis of plots of the electronic energy as a function of the number of electrons, which highlight the extent of symmetry between addition and subtraction. The accuracy of the TDP affinities is closely related to the nature of the orbitals involved in the electron addition and subtraction, being particularly poor in cases where there is a change in principal quantum number, but relatively accurate within a single manifold of orbitals. The analysis is then extended to a consideration of the ground state Mulliken electronegativity and chemical hardness. The findings further emphasize the key role of symmetry in determining the quality of the results.
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Affiliation(s)
- A M Teale
- School of Chemistry, University of Nottingham, University Park, Nottingham, NG7 2RD, UK.
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9
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Xavier S, Periandy S. Spectroscopic (FT-IR, FT-Raman, UV and NMR) investigation on 1-phenyl-2-nitropropene by quantum computational calculations. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2015; 149:216-230. [PMID: 25965169 DOI: 10.1016/j.saa.2015.04.055] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/08/2014] [Revised: 03/25/2015] [Accepted: 04/20/2015] [Indexed: 06/04/2023]
Abstract
In this paper, the spectral analysis of 1-phenyl-2-nitropropene is carried out using the FTIR, FT Raman, FT NMR and UV-Vis spectra of the compound with the help of quantum mechanical computations using ab-initio and density functional theories. The FT-IR (4000-400 cm(-1)) and FT-Raman (4000-100 cm(-1)) spectra were recorded in solid phase, the (1)H and (13)C NMR spectra were recorded in CDCl3 solution phase and the UV-Vis (200-800 nm) spectrum was recorded in ethanol solution phase. The different conformers of the compound and their minimum energies are studied using B3LYP functional with 6-311+G(d,p) basis set and two stable conformers with lowest energy were identified and the same was used for further computations. The computed wavenumbers from different methods are scaled so as to agree with the experimental values and the scaling factors are reported. All the modes of vibrations are assigned and the structure the molecule is analyzed in terms of parameters like bond length, bond angle and dihedral angle predicted by both B3LYP and B3PW91 methods with 6-311+G(d,p) and 6-311++G(d,p) basis sets. The values of dipole moment (μ), polarizability (α) and hyperpolarizability (β) of the molecule are reported, using which the non-linear property of the molecule is discussed. The HOMO-LUMO mappings are reported which reveals the different charge transfer possibilities within the molecule. The isotropic chemical shifts predicted for (1)H and (13)C atoms using gauge invariant atomic orbital (GIAO) theory show good agreement with experimental shifts. NBO analysis is carried out to picture the charge transfer between the localized bonds and lone pairs. The local reactivity of the molecule has been studied using the Fukui function. The thermodynamic properties (heat capacity, entropy and enthalpy) at different temperatures are also calculated.
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Affiliation(s)
- S Xavier
- Department of Physics, St. Joseph College of Arts and Science, Cuddalore, Tamil Nadu, India; Bharathiyar University, Coimbatore, Tamil Nadu, India.
| | - S Periandy
- Department of Physics, Tagore Arts College, Puducherry, India
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10
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Xavier S, Periandy S, Ramalingam S. NBO, conformational, NLO, HOMO-LUMO, NMR and electronic spectral study on 1-phenyl-1-propanol by quantum computational methods. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2015; 137:306-320. [PMID: 25228039 DOI: 10.1016/j.saa.2014.08.039] [Citation(s) in RCA: 96] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/07/2014] [Revised: 07/14/2014] [Accepted: 08/21/2014] [Indexed: 06/03/2023]
Abstract
In this study, FT-IR, FT-Raman, NMR and UV spectra of 1-phenyl-1-propanol, an intermediate of anti-depressant drug fluoxetine, has been investigated. The theoretical vibrational frequencies and optimized geometric parameters have been calculated by using HF and density functional theory with the hybrid methods B3LYP, B3PW91 and 6-311+G(d,p)/6-311++G(d,p) basis sets. The theoretical vibrational frequencies have been found in good agreement with the corresponding experimental data. (1)H and (13)C NMR spectra were recorded and chemical shifts of the molecule were compared to TMS by using the Gauge-Independent Atomic Orbital (GIAO) method. A study on the electronic and optical properties, absorption wavelengths, excitation energy, dipole moment and frontier molecular orbital energies are performed using HF and DFT methods. The thermodynamic properties (heat capacity, entropy and enthalpy) at different temperatures are also calculated. NBO analysis is carried out to picture the charge transfer between the localized bonds and lone pairs. The local reactivity of the molecule has been studied using the Fukui function. NLO properties related to polarizability and hyperpolarizability are also discussed.
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Affiliation(s)
- S Xavier
- Department of Physics, St. Joseph College of Arts and Science, Cuddalore, Tamil Nadu, India; Bharathiyar University, Coimbatore, Tamil Nadu, India.
| | - S Periandy
- Department of Physics, Tagore Arts College, Puducherry, India
| | - S Ramalingam
- Department of Physics, A.V.C. College, Mayiladuthurai, Tamil Nadu, India
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11
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De Proft F, Broeckaert L, Turek J, Růžička A, Willem R. Reactivity of low-oxidation state tin compounds: an overview of the benefits of combining DFT Theory and experimental NMR spectroscopy. CAN J CHEM 2014. [DOI: 10.1139/cjc-2013-0521] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The reactivity and complexation properties of dicoordinated Sn(II) and Sn(0) compounds are reviewed. The (dominant) electrophilicity of the stannylenes was confirmed and quantified through density functional theory (DFT) based reactivity indices. For these compounds, combining theoretical DFT calculations and experimental nuclear magnetic resonance (NMR) spectroscopic results has evidenced their potential to undergo π-complexation from aromatic π clouds in addition to significantly stronger σ-complexation. Moreover, their potential as Lewis bases was scrutinized in their interactions and reactions with iron and tungsten carbonyl Lewis acids. Finally, a prospective comparison of the reactivity of divalent stannylenes and stannylones, with a 0 oxidation state at the Sn atom, is presented.
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Affiliation(s)
- Frank De Proft
- Department of General Chemistry (ALGC), Vrije Universiteit Brussel (VUB), Pleinlaan 2, 1050 Brussels, Belgium
| | - Lies Broeckaert
- Department of General Chemistry (ALGC), Vrije Universiteit Brussel (VUB), Pleinlaan 2, 1050 Brussels, Belgium
| | - Jan Turek
- Department of General and Inorganic Chemistry, Faculty of Chemical Technology, University of Pardubice, Studentská 573, 53210 Pardubice, Czech Republic
| | - Aleš Růžička
- Department of General and Inorganic Chemistry, Faculty of Chemical Technology, University of Pardubice, Studentská 573, 53210 Pardubice, Czech Republic
| | - Rudolph Willem
- Department of Materials and Chemistry (MACH), Vrije Universiteit Brussel (VUB), Pleinlaan 2, 1050 Brussels, Belgium
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12
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Broeckaert L, Frenking G, Geerlings P, De Proft F. Reactivity of Dicoordinated Stannylones (Sn
0
) versus Stannylenes (Sn
II
): An Investigation Using DFT‐Based Reactivity Indices. Chemphyschem 2013; 14:3233-47. [DOI: 10.1002/cphc.201300596] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2013] [Indexed: 11/08/2022]
Affiliation(s)
- Lies Broeckaert
- Department of General Chemistry (ALGC), Vrije Universiteit Brussel (VUB), Pleinlaan 2, 1050 Brussels (Belgium)
| | - Gernot Frenking
- Fachbereich Chemie, Philipps‐Universität Marburg, Hans‐Meerwein‐Straße, 35032 Marburg (Germany)
| | - Paul Geerlings
- Department of General Chemistry (ALGC), Vrije Universiteit Brussel (VUB), Pleinlaan 2, 1050 Brussels (Belgium)
| | - Frank De Proft
- Department of General Chemistry (ALGC), Vrije Universiteit Brussel (VUB), Pleinlaan 2, 1050 Brussels (Belgium)
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13
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A theoretical study on the gas-phase protonation of pyridine and phosphinine derivatives. J Mol Model 2013; 19:4049-58. [PMID: 23892566 DOI: 10.1007/s00894-013-1925-6] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2012] [Accepted: 06/16/2013] [Indexed: 10/26/2022]
Abstract
In this paper, we study the protonation of pyridine and phosphinine derivatives. In particular, the geometries, the amount of charge transfer, and the nature of the created N-H and P-H bonds are discussed, underlying the fundamental differences between the phosphorus and the nitrogen atoms as proton acceptors. Conceptual density functional theory and Bader's quantum theory of atoms-in-molecules are notably used to rationalize these trends and to predict the overall energies of these prototype gas-phase acid-base reactions.
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14
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15
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Pinter B, Nagels N, Herrebout WA, De Proft F. Halogen Bonding from a Hard and Soft Acids and Bases Perspective: Investigation by Using Density Functional Theory Reactivity Indices. Chemistry 2012; 19:519-30. [DOI: 10.1002/chem.201202567] [Citation(s) in RCA: 101] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2012] [Indexed: 11/08/2022]
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17
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Broeckaert L, Geerlings P, Růžička A, Willem R, Proft FD. Can Aromatic π-Clouds Complex Divalent Germanium and Tin Compounds? A DFT Study. Organometallics 2012. [DOI: 10.1021/om100903h] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Affiliation(s)
| | | | - Aleš Růžička
- University of Pardubice, Faculty of Chemical Technology, Department of General and Inorganic Chemistry, Pardubice
53210, Czech Republic
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18
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Fievez T, Geerlings P, Weckhuysen BM, De Proft F. Using DFT in Search for Support Effects During Methanol Oxidation on Supported Molybdenum Oxides. Chemphyschem 2011; 12:3281-90. [DOI: 10.1002/cphc.201100607] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2011] [Revised: 10/07/2011] [Indexed: 11/11/2022]
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19
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Yang ZZ, Wang CS. Atom-Bond Electronegativity Equalization Method and its Applications Based on Density Functional Theory. JOURNAL OF THEORETICAL & COMPUTATIONAL CHEMISTRY 2011. [DOI: 10.1142/s0219633603000434] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
The atom-bond electronegativity equalization method (ABEEM) and its applications for predicting intrinsic properties of large molecules, such as the charge distribution, the molecular energy, the local softness and the Fukui function, the regio- and stereo-selectivity of Diels–Alder reactions, the linear response function, and the charge polarization normal modes have been formulated. The examples show that there is a very good agreement of the ABEEM results with those of the corresponding ab initio quantum chemical calculations, demonstrating the reasonable and possible ABEEM's applications to the large molecular systems.
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Affiliation(s)
- Zhong-Zhi Yang
- Department of Chemistry, Liaoning Normal University, Dalian 116029, China
| | - Chang-Sheng Wang
- Department of Chemistry, Liaoning Normal University, Dalian 116029, China
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20
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Karahan Ö, Işi̇k M, Çifci G, Uǧur İ, Avci D, AvIyente VI. Cyclization tendencies in the free radical polymerization of allyl acrylate derivatives: A computational study. ACTA ACUST UNITED AC 2011. [DOI: 10.1002/pola.24680] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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21
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Hajgató B, De Proft F, Szieberth D, Tozer DJ, Deleuze MS, Geerlings P, Nyulászi L. Bonding in negative ions: the role of d orbitals in the heavy analogues of pyridine and furanradical anions. Phys Chem Chem Phys 2011; 13:1663-8. [DOI: 10.1039/c0cp01151g] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
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22
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Cysewski P. Influence of thermal vibrations on aromaticity of benzene. Phys Chem Chem Phys 2011; 13:12998-3008. [DOI: 10.1039/c1cp20165d] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
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23
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Gutiérrez-Oliva S. Theoretical study of the hydrogen abstraction from vitamin-E analogues. The usefulness of DFT descriptors. J Mol Model 2010; 17:593-8. [PMID: 20517626 DOI: 10.1007/s00894-010-0759-8] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2010] [Accepted: 05/13/2010] [Indexed: 10/19/2022]
Abstract
The activation and reaction energies governing hydrogen atom transfer between α-tocopherol analogues and methylperoxyl radical were determined using the B3LYP/6-311++G(d,p) method. An a priori qualitative estimation of the charge transfer involved in the formation process of the two-fragment reaction between α-tocopherol-like molecules and the methylperoxyl radical was used as a predictive tool to determine antioxidant activity. Consistency between the energetic data and reactivity criterion was nicely reached indicating that the electronic nature of the substituents in the heterocyclic ring in α-tocopherol-like molecules strongly influences the activation and reaction energies.
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Affiliation(s)
- Soledad Gutiérrez-Oliva
- QTC, Departamento de Química-Física, Facultad de Química, Pontificia Universidad Católica de Chile, Casilla 306, Correo 22, Santiago, Chile.
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24
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De Vleeschouwer F, De Proft F, Geerlings P. Conceptual density functional theory based intrinsic radical stabilities: Application to substituted silylenes and p-benzynes. ACTA ACUST UNITED AC 2010. [DOI: 10.1016/j.theochem.2009.11.004] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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25
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Uğur İ, De Vleeschouwer F, Tüzün N, Aviyente V, Geerlings P, Liu S, Ayers PW, De Proft F. Cyclopolymerization Reactions of Diallyl Monomers: Exploring Electronic and Steric Effects Using DFT Reactivity Indices. J Phys Chem A 2009; 113:8704-11. [DOI: 10.1021/jp903371b] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- İlke Uğur
- Chemistry Department, Faculty of Arts and Sciences, Boğaziçi University, 34342 Bebek, Istanbul, Turkey, Eenheid Algemene Chemie, Faculteit Wetenschappen, Vrije Universiteit Brussel, Pleinlaan 2, 1050 Brussels, Belgium, Chemistry Department, Faculty of Science and Letters, Istanbul Technical University, 34469 Maslak, Istanbul, Turkey, Research Computing Center, University of North Carolina, 211 Manning Drive, Chapel Hill, North Carolina 27599-3420, Department of Chemistry, McMaster University, Hamilton,
| | - Freija De Vleeschouwer
- Chemistry Department, Faculty of Arts and Sciences, Boğaziçi University, 34342 Bebek, Istanbul, Turkey, Eenheid Algemene Chemie, Faculteit Wetenschappen, Vrije Universiteit Brussel, Pleinlaan 2, 1050 Brussels, Belgium, Chemistry Department, Faculty of Science and Letters, Istanbul Technical University, 34469 Maslak, Istanbul, Turkey, Research Computing Center, University of North Carolina, 211 Manning Drive, Chapel Hill, North Carolina 27599-3420, Department of Chemistry, McMaster University, Hamilton,
| | - Nurcan Tüzün
- Chemistry Department, Faculty of Arts and Sciences, Boğaziçi University, 34342 Bebek, Istanbul, Turkey, Eenheid Algemene Chemie, Faculteit Wetenschappen, Vrije Universiteit Brussel, Pleinlaan 2, 1050 Brussels, Belgium, Chemistry Department, Faculty of Science and Letters, Istanbul Technical University, 34469 Maslak, Istanbul, Turkey, Research Computing Center, University of North Carolina, 211 Manning Drive, Chapel Hill, North Carolina 27599-3420, Department of Chemistry, McMaster University, Hamilton,
| | - Viktorya Aviyente
- Chemistry Department, Faculty of Arts and Sciences, Boğaziçi University, 34342 Bebek, Istanbul, Turkey, Eenheid Algemene Chemie, Faculteit Wetenschappen, Vrije Universiteit Brussel, Pleinlaan 2, 1050 Brussels, Belgium, Chemistry Department, Faculty of Science and Letters, Istanbul Technical University, 34469 Maslak, Istanbul, Turkey, Research Computing Center, University of North Carolina, 211 Manning Drive, Chapel Hill, North Carolina 27599-3420, Department of Chemistry, McMaster University, Hamilton,
| | - Paul Geerlings
- Chemistry Department, Faculty of Arts and Sciences, Boğaziçi University, 34342 Bebek, Istanbul, Turkey, Eenheid Algemene Chemie, Faculteit Wetenschappen, Vrije Universiteit Brussel, Pleinlaan 2, 1050 Brussels, Belgium, Chemistry Department, Faculty of Science and Letters, Istanbul Technical University, 34469 Maslak, Istanbul, Turkey, Research Computing Center, University of North Carolina, 211 Manning Drive, Chapel Hill, North Carolina 27599-3420, Department of Chemistry, McMaster University, Hamilton,
| | - Shubin Liu
- Chemistry Department, Faculty of Arts and Sciences, Boğaziçi University, 34342 Bebek, Istanbul, Turkey, Eenheid Algemene Chemie, Faculteit Wetenschappen, Vrije Universiteit Brussel, Pleinlaan 2, 1050 Brussels, Belgium, Chemistry Department, Faculty of Science and Letters, Istanbul Technical University, 34469 Maslak, Istanbul, Turkey, Research Computing Center, University of North Carolina, 211 Manning Drive, Chapel Hill, North Carolina 27599-3420, Department of Chemistry, McMaster University, Hamilton,
| | - Paul W. Ayers
- Chemistry Department, Faculty of Arts and Sciences, Boğaziçi University, 34342 Bebek, Istanbul, Turkey, Eenheid Algemene Chemie, Faculteit Wetenschappen, Vrije Universiteit Brussel, Pleinlaan 2, 1050 Brussels, Belgium, Chemistry Department, Faculty of Science and Letters, Istanbul Technical University, 34469 Maslak, Istanbul, Turkey, Research Computing Center, University of North Carolina, 211 Manning Drive, Chapel Hill, North Carolina 27599-3420, Department of Chemistry, McMaster University, Hamilton,
| | - Frank De Proft
- Chemistry Department, Faculty of Arts and Sciences, Boğaziçi University, 34342 Bebek, Istanbul, Turkey, Eenheid Algemene Chemie, Faculteit Wetenschappen, Vrije Universiteit Brussel, Pleinlaan 2, 1050 Brussels, Belgium, Chemistry Department, Faculty of Science and Letters, Istanbul Technical University, 34469 Maslak, Istanbul, Turkey, Research Computing Center, University of North Carolina, 211 Manning Drive, Chapel Hill, North Carolina 27599-3420, Department of Chemistry, McMaster University, Hamilton,
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De Vleeschouwer F, Toro-Labbé A, Gutiérrez-Oliva S, Van Speybroeck V, Waroquier M, Geerlings P, De Proft F. Reversibility from DFT-Based Reactivity Indices: Intramolecular Side Reactions in the Polymerization of Poly(vinyl chloride). J Phys Chem A 2009; 113:7899-908. [DOI: 10.1021/jp900884z] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Freija De Vleeschouwer
- Eenheid Algemene Chemie (ALGC), Vrije Universiteit Brussel (VUB), Pleinlaan 2, 1050 Brussels, Belgium, Laboratorio de Química Teórica Computacional (QTC), Facultad de Química, Pontificia Universidad Católica de Chile, Santiago, Chile, and Center for Molecular Modeling (CMM), Ghent University (UGent), Proeftuinstraat 86, 9000 Gent, Belgium
| | - Alejandro Toro-Labbé
- Eenheid Algemene Chemie (ALGC), Vrije Universiteit Brussel (VUB), Pleinlaan 2, 1050 Brussels, Belgium, Laboratorio de Química Teórica Computacional (QTC), Facultad de Química, Pontificia Universidad Católica de Chile, Santiago, Chile, and Center for Molecular Modeling (CMM), Ghent University (UGent), Proeftuinstraat 86, 9000 Gent, Belgium
| | - Soledad Gutiérrez-Oliva
- Eenheid Algemene Chemie (ALGC), Vrije Universiteit Brussel (VUB), Pleinlaan 2, 1050 Brussels, Belgium, Laboratorio de Química Teórica Computacional (QTC), Facultad de Química, Pontificia Universidad Católica de Chile, Santiago, Chile, and Center for Molecular Modeling (CMM), Ghent University (UGent), Proeftuinstraat 86, 9000 Gent, Belgium
| | - Veronique Van Speybroeck
- Eenheid Algemene Chemie (ALGC), Vrije Universiteit Brussel (VUB), Pleinlaan 2, 1050 Brussels, Belgium, Laboratorio de Química Teórica Computacional (QTC), Facultad de Química, Pontificia Universidad Católica de Chile, Santiago, Chile, and Center for Molecular Modeling (CMM), Ghent University (UGent), Proeftuinstraat 86, 9000 Gent, Belgium
| | - Michel Waroquier
- Eenheid Algemene Chemie (ALGC), Vrije Universiteit Brussel (VUB), Pleinlaan 2, 1050 Brussels, Belgium, Laboratorio de Química Teórica Computacional (QTC), Facultad de Química, Pontificia Universidad Católica de Chile, Santiago, Chile, and Center for Molecular Modeling (CMM), Ghent University (UGent), Proeftuinstraat 86, 9000 Gent, Belgium
| | - Paul Geerlings
- Eenheid Algemene Chemie (ALGC), Vrije Universiteit Brussel (VUB), Pleinlaan 2, 1050 Brussels, Belgium, Laboratorio de Química Teórica Computacional (QTC), Facultad de Química, Pontificia Universidad Católica de Chile, Santiago, Chile, and Center for Molecular Modeling (CMM), Ghent University (UGent), Proeftuinstraat 86, 9000 Gent, Belgium
| | - Frank De Proft
- Eenheid Algemene Chemie (ALGC), Vrije Universiteit Brussel (VUB), Pleinlaan 2, 1050 Brussels, Belgium, Laboratorio de Química Teórica Computacional (QTC), Facultad de Química, Pontificia Universidad Católica de Chile, Santiago, Chile, and Center for Molecular Modeling (CMM), Ghent University (UGent), Proeftuinstraat 86, 9000 Gent, Belgium
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27
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Vleeschouwer FD, Speybroeck VV, Waroquier M, Geerlings P, Proft FD. An Intrinsic Radical Stability Scale from the Perspective of Bond Dissociation Enthalpies: A Companion to Radical Electrophilicities. J Org Chem 2008; 73:9109-20. [DOI: 10.1021/jo802018b] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Freija De Vleeschouwer
- Eenheid Algemene Chemie (ALGC), Faculteit Wetenschappen, Vrije Universiteit Brussel (VUB), Pleinlaan 2, 1050 Brussels, Belgium, and Center for Molecular Modeling (CMM), Ghent University (UG), Proeftuinstraat 86, 9000 Gent, Belgium
| | - Veronique Van Speybroeck
- Eenheid Algemene Chemie (ALGC), Faculteit Wetenschappen, Vrije Universiteit Brussel (VUB), Pleinlaan 2, 1050 Brussels, Belgium, and Center for Molecular Modeling (CMM), Ghent University (UG), Proeftuinstraat 86, 9000 Gent, Belgium
| | - Michel Waroquier
- Eenheid Algemene Chemie (ALGC), Faculteit Wetenschappen, Vrije Universiteit Brussel (VUB), Pleinlaan 2, 1050 Brussels, Belgium, and Center for Molecular Modeling (CMM), Ghent University (UG), Proeftuinstraat 86, 9000 Gent, Belgium
| | - Paul Geerlings
- Eenheid Algemene Chemie (ALGC), Faculteit Wetenschappen, Vrije Universiteit Brussel (VUB), Pleinlaan 2, 1050 Brussels, Belgium, and Center for Molecular Modeling (CMM), Ghent University (UG), Proeftuinstraat 86, 9000 Gent, Belgium
| | - Frank De Proft
- Eenheid Algemene Chemie (ALGC), Faculteit Wetenschappen, Vrije Universiteit Brussel (VUB), Pleinlaan 2, 1050 Brussels, Belgium, and Center for Molecular Modeling (CMM), Ghent University (UG), Proeftuinstraat 86, 9000 Gent, Belgium
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28
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Hajgató B, Deleuze MS, Tozer DJ, De Proft F. A benchmark theoretical study of the electron affinities of benzene and linear acenes. J Chem Phys 2008; 129:084308. [DOI: 10.1063/1.2967182] [Citation(s) in RCA: 88] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023] Open
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29
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De Proft F, Chattaraj PK, Ayers PW, Torrent-Sucarrat M, Elango M, Subramanian V, Giri S, Geerlings P. Initial Hardness Response and Hardness Profiles in the Study of Woodward–Hoffmann Rules for Electrocyclizations. J Chem Theory Comput 2008; 4:595-602. [DOI: 10.1021/ct700289p] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- F. De Proft
- Eenheid Algemene Chemie (ALGC), Vrije Universiteit Brussel (VUB), Faculteit Wetenschappen, Pleinlaan 2, 1050 Brussels, Belgium, Department of Chemistry and Center for Theoretical Studies, Indian Institute of Technology, Kharagpur 721302, India, Department of Chemistry, McMaster University, Hamilton, Ontario, Canada L8S 4M1, and Chemical Laboratory, Central Leather Research Institute, Adyar, Chennai 600020, India
| | - P. K. Chattaraj
- Eenheid Algemene Chemie (ALGC), Vrije Universiteit Brussel (VUB), Faculteit Wetenschappen, Pleinlaan 2, 1050 Brussels, Belgium, Department of Chemistry and Center for Theoretical Studies, Indian Institute of Technology, Kharagpur 721302, India, Department of Chemistry, McMaster University, Hamilton, Ontario, Canada L8S 4M1, and Chemical Laboratory, Central Leather Research Institute, Adyar, Chennai 600020, India
| | - P. W. Ayers
- Eenheid Algemene Chemie (ALGC), Vrije Universiteit Brussel (VUB), Faculteit Wetenschappen, Pleinlaan 2, 1050 Brussels, Belgium, Department of Chemistry and Center for Theoretical Studies, Indian Institute of Technology, Kharagpur 721302, India, Department of Chemistry, McMaster University, Hamilton, Ontario, Canada L8S 4M1, and Chemical Laboratory, Central Leather Research Institute, Adyar, Chennai 600020, India
| | - M. Torrent-Sucarrat
- Eenheid Algemene Chemie (ALGC), Vrije Universiteit Brussel (VUB), Faculteit Wetenschappen, Pleinlaan 2, 1050 Brussels, Belgium, Department of Chemistry and Center for Theoretical Studies, Indian Institute of Technology, Kharagpur 721302, India, Department of Chemistry, McMaster University, Hamilton, Ontario, Canada L8S 4M1, and Chemical Laboratory, Central Leather Research Institute, Adyar, Chennai 600020, India
| | - M. Elango
- Eenheid Algemene Chemie (ALGC), Vrije Universiteit Brussel (VUB), Faculteit Wetenschappen, Pleinlaan 2, 1050 Brussels, Belgium, Department of Chemistry and Center for Theoretical Studies, Indian Institute of Technology, Kharagpur 721302, India, Department of Chemistry, McMaster University, Hamilton, Ontario, Canada L8S 4M1, and Chemical Laboratory, Central Leather Research Institute, Adyar, Chennai 600020, India
| | - V. Subramanian
- Eenheid Algemene Chemie (ALGC), Vrije Universiteit Brussel (VUB), Faculteit Wetenschappen, Pleinlaan 2, 1050 Brussels, Belgium, Department of Chemistry and Center for Theoretical Studies, Indian Institute of Technology, Kharagpur 721302, India, Department of Chemistry, McMaster University, Hamilton, Ontario, Canada L8S 4M1, and Chemical Laboratory, Central Leather Research Institute, Adyar, Chennai 600020, India
| | - S. Giri
- Eenheid Algemene Chemie (ALGC), Vrije Universiteit Brussel (VUB), Faculteit Wetenschappen, Pleinlaan 2, 1050 Brussels, Belgium, Department of Chemistry and Center for Theoretical Studies, Indian Institute of Technology, Kharagpur 721302, India, Department of Chemistry, McMaster University, Hamilton, Ontario, Canada L8S 4M1, and Chemical Laboratory, Central Leather Research Institute, Adyar, Chennai 600020, India
| | - P. Geerlings
- Eenheid Algemene Chemie (ALGC), Vrije Universiteit Brussel (VUB), Faculteit Wetenschappen, Pleinlaan 2, 1050 Brussels, Belgium, Department of Chemistry and Center for Theoretical Studies, Indian Institute of Technology, Kharagpur 721302, India, Department of Chemistry, McMaster University, Hamilton, Ontario, Canada L8S 4M1, and Chemical Laboratory, Central Leather Research Institute, Adyar, Chennai 600020, India
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30
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Geerlings P, De Proft F. Conceptual DFT: the chemical relevance of higher response functions. Phys Chem Chem Phys 2008; 10:3028-42. [PMID: 18688366 DOI: 10.1039/b717671f] [Citation(s) in RCA: 192] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
In recent years conceptual density functional theory offered a perspective for the interpretation/prediction of experimental/theoretical reactivity data on the basis of a series of response functions to perturbations in the number of electrons and/or external potential. This approach has enabled the sharp definition and computation, from first principles, of a series of well-known but sometimes vaguely defined chemical concepts such as electronegativity and hardness. In this contribution, a short overview of the shortcomings of the simplest, first order response functions is illustrated leading to a description of chemical bonding in a covalent interaction in terms of interacting atoms or groups, governed by electrostatics with the tendency to polarize bonds on the basis of electronegativity differences. The second order approach, well known until now, introduces the hardness/softness and Fukui function concepts related to polarizability and frontier MO theory, respectively. The introduction of polarizability/softness is also considered in a historical perspective in which polarizability was, with some exceptions, mainly put forward in non covalent interactions. A particular series of response functions, arising when the changes in the external potential are solely provoked by changes in nuclear configurations (the "R-analogues") are also systematically considered. The main part of the contribution is devoted to third order response functions which, at first sight, may be expected not to yield chemically significant information, as turns out to be for the hyperhardness. A counterexample is the dual descriptor and its R analogue, the initial hardness response, which turns out to yield a firm basis to regain the Woodward-Hoffmann rules for pericyclic reactions based on a density-only basis, i.e. without involving the phase, sign, symmetry of the wavefunction. Even the second order nonlinear response functions are shown possibly to bear interesting information, e.g. on the local and global polarizability. Its derivatives may govern the influence of charge on the polarizability, the R-analogues being the nuclear Fukui function and the quadratic and cubic force constants. Although some of the higher order derivatives may be difficult to evaluate a comparison with the energy expansion used in spectroscopy in terms of nuclear displacements, nuclear magnetic moments, electric and magnetic fields leads to the conjecture that, certainly cross terms may contain new, intricate information for understanding chemical reactivity.
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Affiliation(s)
- P Geerlings
- Eenheid Algemene Chemie (ALGC), Faculty of Sciences, Vrije Universiteit Brussel (Free University of Brussels - VUB), Pleinlaan 2, 1050, Brussels.
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31
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Núñez-Zarur F, Vivas-Reyes R. Ab initio study of luminescent substituted 8-hydroxyquinoline metal complexes with application in organic light emitting diodes. ACTA ACUST UNITED AC 2008. [DOI: 10.1016/j.theochem.2007.10.036] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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32
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Pintér B, De Proft F, Veszprémi T, Geerlings P. Theoretical Study of the Orientation Rules in Photonucleophilic Aromatic Substitutions. J Org Chem 2008; 73:1243-52. [DOI: 10.1021/jo701392m] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- B. Pintér
- Inorganic and Analytical Chemistry Department, Budapest University of Technology and Economics (BUTE), Szent Gellért tér 4, 1521 Budapest, Hungary, and Eenheid Algemene Chemie (ALGC), Faculteit Wetenschappen, Vrije Universiteit Brussel (VUB), Pleinlaan 2, 1050 Brussels, Belgium
| | - F. De Proft
- Inorganic and Analytical Chemistry Department, Budapest University of Technology and Economics (BUTE), Szent Gellért tér 4, 1521 Budapest, Hungary, and Eenheid Algemene Chemie (ALGC), Faculteit Wetenschappen, Vrije Universiteit Brussel (VUB), Pleinlaan 2, 1050 Brussels, Belgium
| | - T. Veszprémi
- Inorganic and Analytical Chemistry Department, Budapest University of Technology and Economics (BUTE), Szent Gellért tér 4, 1521 Budapest, Hungary, and Eenheid Algemene Chemie (ALGC), Faculteit Wetenschappen, Vrije Universiteit Brussel (VUB), Pleinlaan 2, 1050 Brussels, Belgium
| | - P. Geerlings
- Inorganic and Analytical Chemistry Department, Budapest University of Technology and Economics (BUTE), Szent Gellért tér 4, 1521 Budapest, Hungary, and Eenheid Algemene Chemie (ALGC), Faculteit Wetenschappen, Vrije Universiteit Brussel (VUB), Pleinlaan 2, 1050 Brussels, Belgium
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Tozer DJ, De Proft F. Modeling temporary anions in density functional theory: calculation of the Fukui function. J Chem Phys 2007; 127:034108. [PMID: 17655432 DOI: 10.1063/1.2751158] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
Two approaches are investigated for modeling electron densities of temporary anions in density functional theory (DFT). Both rely on an artificial binding of the excess electron, in one case by a compact basis set and in the other by a potential wall. The key feature of the calculations is that the degree of binding is controlled in both cases by knowledge of the negative electron affinity of the corresponding neutral, approximated in terms of DFT local functional frontier orbital eigenvalues and vertical ionization potential, A=-(epsilon(LUMO)+epsilon(HOMO))-I. To illustrate the two approaches, Fukui functions for nucleophilic attack are determined in four molecules with increasingly negative electron affinities. They yield very similar results, which are notably different to those determined without artificial electron binding. The use of a potential wall has the attractive feature that large, diffuse basis sets can be used, avoiding the need for a compact basis, tailored to a particular molecule.
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Affiliation(s)
- David J Tozer
- Department of Chemistry, University of Durham, South Road, Durham DH1 3LE, United Kingdom.
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Janssens S, Van Alsenoy C, Geerlings P. Molecular Quantum Similarity and Chirality: Enantiomers with Two Asymmetric Centra. J Phys Chem A 2007; 111:3143-51. [PMID: 17394298 DOI: 10.1021/jp070479i] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Molecular quantum similarity is evaluated for enantiomers possessing two asymmetric carbon atoms, namely halogen substituted ethanes. This study is an extension of previous work performed on molecules with a single asymmetric carbon atom and molecules possessing a chiral axis. Global similarity and its local counterpart based on the Hirshfeld partitioning are evaluated. By these means we quantify the dissimilarity of enantiomers and illustrate Mezey's holographic electron density theorem in chiral systems. Furthermore, the relation between the optical activity and the dissimilarity is studied. Special attention is drawn to the meso compounds, since these isomers enable us to examine local chirality in an achiral system.
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Affiliation(s)
- Sara Janssens
- Eenheid Algemene Chemie (ALGC), Faculteit Wetenschappen, Free University of Brussels (VUB), Pleinlaan 2, B-1050 Brussels, Belgium.
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Geerlings P, Proft FD, Ayers P. Chapter 1 Chemical reactivity and the shape function. THEORETICAL AND COMPUTATIONAL CHEMISTRY 2007. [DOI: 10.1016/s1380-7323(07)80002-1] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
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36
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Pintér B, De Proft F, Van Speybroeck V, Hemelsoet K, Waroquier M, Chamorro E, Veszprémi T, Geerlings P. Spin-Polarized Conceptual Density Functional Theory Study of the Regioselectivity in Ring Closures of Radicals. J Org Chem 2006; 72:348-56. [PMID: 17221949 DOI: 10.1021/jo0613885] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The regioselectivity of ring-forming radical reactions is investigated within the framework of the so-called spin-polarized conceptual density functional theory. Two different types of cyclizations were studied. First, a series of model reactions of alkyl- and acyl-substituted radicals were investigated. Next, attention was focused on the radical cascade cyclizations of N-alkenyl-2-aziridinylmethyl radicals (a three-step mechanism). In both of these reactions, the approaching radical (carbon or nitrogen centered) adds to a carbon-carbon double bond within the same molecule to form a radical ring compound. In this process, the number of electrons is changing from a local point of view (a charge transfer occurs from one part of the molecule to another one) at constant global spin number Ns (both the reactant and the product ring compound are in the doublet state). It is shown that the experimentally observed regioselectivities for these ring-closure steps can be predicted using the spin-polarized Fukui functions for radical attack, f0NN(r).
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Affiliation(s)
- B Pintér
- Inorganic Chemistry Department, Budapest University of Technology and Economics (BUTE), Szent Gellért tér 4, 1521 Budapest, Hungary
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De Proft F, Ayers PW, Fias S, Geerlings P. Woodward-Hoffmann rules in density functional theory: Initial hardness response. J Chem Phys 2006; 125:214101. [PMID: 17166009 DOI: 10.1063/1.2387953] [Citation(s) in RCA: 53] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
The Woodward-Hoffmann rules for pericyclic reactions, a fundamental set of reactivity rules in organic chemistry, are formulated in the language of conceptual density functional theory (DFT). DFT provides an elegant framework to introduce chemical concepts and principles in a quantitative manner, partly because it is formulated without explicit reference to a wave function, on whose symmetry properties the Woodward-Hoffmann [J. Am. Chem. Soc. 87, 395 (1965)] rules are based. We have studied the initial chemical hardness response using a model reaction profile for two prototypical pericyclic reactions, the Diels-Alder cycloaddition of 1,3-butadiene to ethylene and the addition of ethylene to ethylene, both in the singlet ground state and in the first triplet excited state. For the reaction that is thermally allowed but photochemically forbidden, the initial hardness response is positive along the singlet reaction profile. (By contrast, for the triplet reaction profile, a negative hardness response is observed.) For the photochemically allowed, thermally forbidden reaction, the behavior of the chemical hardness along the initial stages of the singlet and triplet reaction profiles is reversed. This constitutes a first step in showing that chemical concepts from DFT can be invoked to explain results that would otherwise require invoking the phase of the wave function.
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Affiliation(s)
- Frank De Proft
- Eenheid Algemene Chemie, Vrije Universiteit Brussel (VUB), Faculteit Wetenschappen, Pleinlaan 2, 1050 Brussels, Belgium
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Safi B, Mertens J, De Proft F, Geerlings P. A Computational and Conceptual Density Functional Theory Study of the Properties of Re and Tc Tricarbonyl Complexes. J Phys Chem A 2006; 110:9240-6. [PMID: 16854039 DOI: 10.1021/jp062532t] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
A computational and conceptual density functional study has been performed on metal tricarbonyl complexes (MTC) of both Re(I) and Tc(I). The fully optimized complexes of fac-[Tc(OH(2))(CO(3))](+) and mer-[Tc(OH(2))(CO(3))](+) show geometries that compare favorably with the X-ray data. These structures were used as a starting point to investigate the relative stability of MTC complexes with various ligands containing combinations of N, O, and S as chelating atoms and to evaluate the stabilizing/destabilizing influence of these ligands. Both for Tc and for Re complexes the nitrogen content turns out to be decisive in the stability of the metaltricarbonyl complexes, the finer details being determined by the hardness sequence N > O > S. As the core of the complexes, [(M(CO)(3)(+)], is hard, the main ordering parameter is changed as compared to our previous studies on Tc(V) [3+1] complexes where the number of sulfur atoms was decisive in accordance with the much softer character of the MOCl core. All results are successfully interpreted in terms of the hard and soft acids and bases principle (HSAB) at the local level.
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Affiliation(s)
- B Safi
- General Chemistry (ALGC), Faculty of Sciences, Vrije Universiteit Brussel, Pleinlaan 2, 1050 Brussels, Belgium
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Geerlings P, Vos A, Schoonheydt R. A computational and conceptual DFT approach to the kinetics of acid zeolite catalyzed electrophilic aromatic substitution reactions. ACTA ACUST UNITED AC 2006. [DOI: 10.1016/j.theochem.2005.10.050] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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Shetty S, Kar R, Kanhere DG, Pal S. Intercluster Reactivity of Metalloaromatic and Antiaromatic Compounds and Their Applications in Molecular Electronics: A Theoretical Investigation. J Phys Chem A 2005; 110:252-6. [PMID: 16392862 DOI: 10.1021/jp053818l] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Local reactivity descriptors, such as the condensed local softness and Fukui function, have been employed to investigate the intercluster reactivity of the metalloaromatic (Al4Li- and Al4Na-) and antiaromatic (Al4Li4 and Al4Na4) compounds. We have used the concept of group softness and group Fukui function to characterize the strength of the nucleophilicity (ability to donate electrons) of the Al4 unit in these compounds. The aim of this work is to understand the enhanced efficiency of the electron injection of the Al-Li cathode in the organic light emitting diode due to the formation of Al-Li clusters at the interface. Our analysis shows that the Al4 unit of the Al4Li- cluster has the highest nucleophilicity compared to the other clusters. Hence, we believe that the formation of the Al4Li- type of metalloaromatic clusters would be responsible for the increase in the efficiency of the electron injection of the Al-Li cathode.
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Affiliation(s)
- Sharan Shetty
- Theoretical Chemistry Group, Physical Chemistry Division, National Chemical Laboratory, and Department of Physics and Centre for Modeling and Simulation, University of Pune, Pune-411007, India
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Pasha FA, Srivastava HK, Singh PP. Comparative QSAR study of phenol derivatives with the help of density functional theory. Bioorg Med Chem 2005; 13:6823-9. [PMID: 16169734 DOI: 10.1016/j.bmc.2005.07.064] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2005] [Revised: 07/23/2005] [Accepted: 07/25/2005] [Indexed: 10/25/2022]
Abstract
Quantum chemical reactivity descriptors based QSAR study of 50 phenol derivatives is presented in this paper. Four different methods have been employed to certify the reliability of QSAR study. The molecular weight, hardness, chemical potential, total energy, and electrophilicity index provide valuable information and have a significant role in the assessment of the toxicity of phenols. The first model has been drawn up with the help of AM1 calculations and in this model the correlation coefficient r2 is 0.88 and the cross-validation coefficient r(cv)2 is 0.78. Second and third models have been designed with the PM3 and PM5 calculations, respectively. The values of correlation coefficient r2 and cross-validation coefficient r(cv)2 in the second case are 0.85 and .070, while in the third case they are 0.85 and 0.71. Finally, the DFT calculations have been made for the same series of compounds by using a B88-PW91 GGA energy functional with the DZVP basis set. The DFT models have a higher predictive power than AM1, PM3, and PM5 methods, and the reliability of this model is clear from its correlation coefficient r2 0.91 and cross-validation coefficient r(cv)2 0.88. This study is also helpful in determining the effect of any particular phenol derivative of this series over Tetrahymena pyriformis.
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Affiliation(s)
- F A Pasha
- Department of Chemistry, Bareilly College Bareilly, UP, India.
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Cruz VL, Ramos J, Martinez S, Muñoz-Escalona A, Martinez-Salazar J. Structure−Activity Relationship Study of the Metallocene Catalyst Activity in Ethylene Polymerization. Organometallics 2005. [DOI: 10.1021/om050458f] [Citation(s) in RCA: 55] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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43
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Tozer DJ, De Proft F. Computation of the Hardness and the Problem of Negative Electron Affinities in Density Functional Theory. J Phys Chem A 2005; 109:8923-9. [PMID: 16834296 DOI: 10.1021/jp053504y] [Citation(s) in RCA: 144] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The absolute hardness in density functional theory (DFT) is discussed, emphasizing the charge-transfer excitation interpretation. Direct evaluation from the computed ionization potential and electron affinity is intrinsically problematic when the affinity is negative; the calculated affinity exhibits a strong basis set dependence, becoming near zero as diffuse functions are added. An alternative Koopmans-based approximation using local functional eigenvalues uniformly and significantly underestimates the hardness. A simple correction to the Koopmans expression is highlighted on the basis of a consideration of the integer discontinuity. The resulting hardness expression does not require the explicit computation of the affinity and has a straightforward interpretation in terms of the electronegativity. The correction eliminates the underestimation and gives hardness values that do not degrade as the electron affinity becomes more negative. For systems with large negative affinities, the values are an improvement over those from the other approaches. The success can be traced to an implicit, unconventional approximation for the electron affinity, which outperforms the standard approach when the affinity is significantly negative and which does not break down as the basis set becomes more diffuse.
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Affiliation(s)
- David J Tozer
- Department of Chemistry, University of Durham, South Road, Durham DH1 3LE, U.K.
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Pintér B, De Proft F, Veszprémi T, Geerlings P. Regioselectivity in the [2 + 2] cyclo-addition reaction of triplet carbonyl compounds to substituted alkenes (Paterno-Büchi reaction): A spin-polarized conceptual DFT approach. J CHEM SCI 2005. [DOI: 10.1007/bf02708363] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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De Proft F, Fias S, Van Alsenoy C, Geerlings P. Spin-Polarized Conceptual Density Functional Theory Study of the Regioselectivity in the [2+2] Photocycloaddition of Enones to Substituted Alkenes. J Phys Chem A 2005; 109:6335-43. [PMID: 16833976 DOI: 10.1021/jp050773f] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
A study of the regioselectivity of the photochemical [2+2] cycloaddition of triplet enones with a series of ground-state electron-rich and electron-poor alkenes using density functional theory (DFT)-based reactivity descriptors is presented. Using the concepts of local softness combined with a local hard and soft acids and bases principle and a softness matching approach, the regioselectivity of this reaction can only be explained in the case of the interaction of the triplet enones with electron-rich alkenes. In the next part, the regioselectivity was assessed within the framework of conceptual spin-polarized conceptual DFT, considering response functions of the system's external potential v, number of electrons N, and spin number NS (with NS being the difference between the number of alpha and beta electrons in the spin-polarized system). Within this theory, the concepts of local spin philicity and donicity are introduced. Using the spin philicity concept, the regioselectivity can almost be completely interpreted as resulting from the interaction of the site on the alkene with the highest spin philicity (i.e., lowest destabilization upon increasing spin number) with the site showing the highest change of spin number on the enone expected to result in the largest stabilization of this species.
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Affiliation(s)
- F De Proft
- Eenheid Algemene Chemie (ALGC), Vrije Universiteit Brussel (VUB), Faculteit Wetenschappen, Pleinlaan 2, 1050 Brussels, Belgium
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47
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Torrent-Sucarrat M, De Proft F, Geerlings P. Stiffness and Raman Intensity: a Conceptual and Computational DFT Study. J Phys Chem A 2005; 109:6071-6. [PMID: 16833943 DOI: 10.1021/jp044150y] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
A DFT-based reactivity descriptor, the nuclear stiffness, is related to the Raman scattering intensity, which is experimentally accessible. The application of this new relationship obtained within certain approximations has been checked in two different sets of molecules. First, we study a favorable case, where the contribution of the anisotropy to the Raman intensity is zero (symmetric stretching mode in 15 tetrahedral molecules). Second, we consider a "worst" case scenario, where the anisotropy contribution can be expected to be important (stretching mode in 32 diatomic molecules). The numerical results clearly show a relationship between stiffness and Raman intensity reflecting the expected anisotropy influence.
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Affiliation(s)
- Miquel Torrent-Sucarrat
- Eenheid Algemene Chemie, Faculteit Wetenschappen, Vrije Universiteit Brussel (VUB), Pleinlaan 2, Brussels, Belgium
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48
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Giju KT, De Proft F, Geerlings P. Comprehensive Study of Density Functional Theory Based Properties for Group 14 Atoms and Functional Groups, −XY3 (X = C, Si, Ge, Sn, Pb, Element 114; Y = CH3, H, F, Cl, Br, I, At). J Phys Chem A 2005; 109:2925-36. [PMID: 16833611 DOI: 10.1021/jp050463x] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
All electron nonrelativistic and relativistic density functional theory calculations at the BP86/QZ4P (Slater type) level are reported for a set of fundamentally useful DFT based reactivity descriptors for group 14 elements (C, Si, Ge, Sn, Pb, Element 114 (abbreviated as Uuq)) and functional groups, -XY3 (X = C, Si, Ge, Sn, Pb, Element 114 (Uuq); Y = CH3, H, F, Cl, Br, I, At); these include electronegativity (chi), chemical hardness (eta), global softness (S), and electrophilicity index (omega). This approach permits an evaluation of the discrepancies in electronegativity scales and associated properties at uniform levels affording a nonempirical analysis for the first time. The vital importance of the spin-orbit interaction, in addition to the scalar relativistic terms, is demonstrated in reproducing the experimental trends on going from top to bottom of the group. The order for isolated atoms is altered when passing to -XY3 groups for all of the properties studied. For example, the calculated atomic electronegativities show a uniform decrease from C to Pb increasing again to Uuq as verified in the experimental data for C-Pb but at variance with several other scales. The sequence for functional groups is different and in accordance with experimental NMR data where available. The experimental hardness sequence for the isolated atoms (C > Pb > Si > Ge > Sn) is opposed to the trends of decreasing hardness on going down the periodic table as is found, e.g., in the halogen group and confirmed by this study. The -XY3 functional groups however follow the C > Si > Ge > Sn > Pb sequence. The recently developed electrophilicity index (omega) has been shown to be highly correlated with the electron affinity rather than the electronegativity. Finally, regression analyses that discriminate between the properties are carried out to investigate the nature of additivity of atomic contributions in functional group properties.
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Affiliation(s)
- Kalathingal T Giju
- Contribution from the Eenheid Algemene Chemie (ALGC), Vrije Universiteit Brussel (VUB), Faculteit Wetenschappen, Pleinlaan 2, 1050 Brussels, Belgium
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Oláh J, De Proft F, Veszprémi T, Geerlings P. Hard−Soft Acid−Base Interactions of Silylenes and Germylenes. J Phys Chem A 2005; 109:1608-15. [PMID: 16833484 DOI: 10.1021/jp0468556] [Citation(s) in RCA: 66] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
A detailed investigation of the electrophilic and nucleophilic character of singlet silylenes and germylenes, divalent compounds of silicon and germanium, respectively, substituted by first- and second-row elements is presented. In a first part, the Lewis acid properties of these compounds were studied through their complexation reaction with the Lewis bases NH3, PH3, and AsH3. The results indicate that this complexation is most favorable with the hardest base NH3, classifying these compounds as hard Lewis acids. This is confirmed by the linear correlation between the interaction energies and the value of the electrostatic potential, used as an approximation to the local hardness, near the empty p orbital of these compounds, indicating a charge-controlled interaction in the complex. Also the electrophilicity index, proposed by Parr et al., computed both at the global and the local level, correlates linearly with the complexation energies of the compounds with NH3. The Lewis base character of these silylenes has been investigated, through their interaction with the acids BH3 and AlH3. Also in this case, the electrostatic potential can be used to probe the reactivity of the compounds. It will finally be demonstrated that an increasing stability of the silylenes and germylenes is accompanied by an increase in their nucleophilicity and a decrease of the electrophilicity.
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Affiliation(s)
- Julianna Oláh
- Vrije Universiteit Brussel (VUB), General Chemistry Department (ALGC), Pleinlaan 2, B-1050, Brussels, Belgium
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50
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Safi B, Mertens J, De Proft F, Alberto R, Geerlings P. Relative Stability of Mixed [3 + 1] Tc and Re Complexes: a Computational and Conceptual DFT Study. J Phys Chem A 2005; 109:1944-51. [PMID: 16833528 DOI: 10.1021/jp045448r] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
A computational and conceptual density-functional study has been performed on various [3 + 1] complexes of both Re(V) and Tc(V). The fully optimized complexes chloro(3-thiapentane-1,5-dithiolato)oxorhenium(V) and chloro(3-thiapentane-1,5-dithiolato)oxotechnetium(V) show geometries that compare favorably with the X-ray data. These structures were used as a starting point to investigate the relative stability of Tc(V) and Re(V) complexes with various ligands containing combinations of N, O, and S as chelating atoms and to evaluate the stabilizing/destabilizing influence of these N, O, and S combinations. For both Tc and Re complexes, the S content (number and position of S atoms) together with the presence of an oxygen as the central chelating atom turns out to be decisive in the stability of the tridentate complexes, the latter factor being strongly destabilizing and the former stabilizing. The stabilization sequences for both Tc and Re are shown to be identical in the gas phase and in aqueous solutions treated in a polarizable continuum model. The Re(V) complexes are found to be more stable than their Tc(V) analogues. All of the results are successfully interpreted in terms of the hard and soft acids and bases principle, applied at the local level. For this purpose, a softness value for Tc is obtained by interpolating softness trends in neighboring elements of rows 5 and 6 in the periodic table.
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Affiliation(s)
- B Safi
- General Chemistry (ALGC), Faculty of Sciences, Vrije Universiteit Brussel, Pleinlaan 2, 1050 Brussels, Belgium
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