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Pansini F, de Campos M, Neto A, Sergio C. Theoretical study of the electronic structure and electrical properties of Al-doped niobium clusters. Chem Phys 2020. [DOI: 10.1016/j.chemphys.2020.110778] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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2
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Zhang XX, Qi H, Lu MH, Yang SQ, Li P, Piao HL, Han KL. Semi-Quantitatively Designing Two-Photon High-Performance Fluorescent Probes for Glutathione S-Transferases. RESEARCH 2020; 2020:7043124. [PMID: 32377639 PMCID: PMC7114728 DOI: 10.34133/2020/7043124] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/21/2019] [Accepted: 02/18/2020] [Indexed: 01/09/2023]
Abstract
Glutathione S-transferases (GSTs), detoxification enzymes that catalyze the addition of glutathione (GSH) to diverse electrophilic molecules, are often overexpressed in various tumor cells. While fluorescent probes for GSTs have often adopted the 2,4-dinitrobenzenesulfonyl (DNs) group as the receptor unit, they usually suffer from considerable background reaction noise with GSH due to excessive electron deficiency. However, weakening this reactivity is generally accompanied by loss of sensitivity for GSTs, and therefore, finely turning down the reactivity while maintaining certain sensitivity is critical for developing a practical probe. Here, we report a rational semiquantitative strategy for designing such a practical two-photon probe by introducing a parameter adopted from the conceptual density functional theory (CDFT), the local electrophilicity ω k , to characterize this reactivity. As expected, kinetic studies established ω k as efficient to predict the reactivity with GSH, and probe NI3 showing the best performance was successfully applied to detecting GST activities in live cells and tissue sections with high sensitivity and signal-to-noise ratio. Photoinduced electron transfer of naphthalimide-based probes, captured by femtosecond transient absorption for the first time and unraveled by theoretical calculations, also contributes to the negligible background noise.
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Affiliation(s)
- Xue-Xiang Zhang
- State Key Laboratory of Molecular Reaction Dynamics, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China
| | - Huan Qi
- CAS Key Laboratory of Separation Science for Analytical Chemistry, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China
| | - Mei-Heng Lu
- State Key Laboratory of Molecular Reaction Dynamics, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China
| | - Song-Qiu Yang
- State Key Laboratory of Molecular Reaction Dynamics, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China
| | - Peng Li
- Institute of Molecular Sciences and Engineering, Shandong University, Qingdao 266237, China
| | - Hai-Long Piao
- CAS Key Laboratory of Separation Science for Analytical Chemistry, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China
| | - Ke-Li Han
- State Key Laboratory of Molecular Reaction Dynamics, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China.,Institute of Molecular Sciences and Engineering, Shandong University, Qingdao 266237, China
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3
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Rose Tale, Fazaeli R, Marjani A. Pseudo-Jahn–Teller Effect in Benzene Ring Analogues of Fourth Group Elements. RUSSIAN JOURNAL OF PHYSICAL CHEMISTRY A 2019. [DOI: 10.1134/s003602441911030x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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4
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Pansini FNN, de Souza FAL, Campos CT. Molecules under external electric field: On the changes in the electronic structure and validity limits of the theoretical predictions. J Comput Chem 2018; 39:1561-1567. [PMID: 29676469 DOI: 10.1002/jcc.25229] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2018] [Revised: 03/01/2018] [Accepted: 03/25/2018] [Indexed: 11/07/2022]
Abstract
A detailed analysis of the electronic structure of the ground and first excited spin state of three diatomic molecules ( N2, BH and CO) under static applied electric field is performed at CCSD(T), DFT, MRCI and MRCI(Q) levels of theory. Our findings have revealed that by boosting the applied field one induces changes in the occupation numbers of molecular orbitals, giving rise to changes in the equilibrium geometry and in the HOMO-LUMO energy gap. Specifically, singlet to triplet spin transition can be induced by increasing the applied electric field beyond a critical value. Accordingly, affecting the accuracy of the widely used expression of energy expanded in Taylor series with respect to the applied electric field. © 2018 Wiley Periodicals, Inc.
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Affiliation(s)
- F N N Pansini
- Departamento de Física, Universidade Federal do Espírito Santo, Av. Fernando Ferrari, 514, Vitória-ES, 29075-910, Brazil
| | - F A L de Souza
- Instituto Federal do Espírito Santo, Ibatiba, 29395-000, Brazil
| | - C T Campos
- Instituto Federal do Espírito Santo, Vitória, 29040-780, Brazil
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5
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Pansini FNN, Neto AC, de Campos M, de Aquino RM. Effects of All-Electron Basis Sets and the Scalar Relativistic Corrections in the Structure and Electronic Properties of Niobium Clusters. J Phys Chem A 2017; 121:5728-5734. [PMID: 28686436 DOI: 10.1021/acs.jpca.7b04600] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
In this paper, an augmented all-electron double-ζ basis set is used in calculations of the structure and electronic properties of small niobium clusters. The B3PW91 and M06 DFT functionals with and without second order Douglas-Kroll-Hess (DKH) scalar relativistic corrections are also utilized. Furthermore, an additional d Gaussian type function is introduced in the standard basis sets in order to improve the description of the clusters orbitals in the valence band. Our findings show that the extra d function is important to yield accurate results of electronic properties and, in addition, the DKH corrections can be relevant when the all-electron basis sets are used in the calculations. Our best results are obtained with the M06 functional together with the DKH second order corrections and with the extra d function added to the all-electron basis set.
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Affiliation(s)
- F N N Pansini
- Departamento de Física, Universidade Federal do Espírito Santo , 29075-910 Vitória, Brazil
| | - A C Neto
- Departamento de Física, Universidade Federal do Espírito Santo , 29075-910 Vitória, Brazil
| | - M de Campos
- Departamento de Física, Universidade Federal de Roraima , 69310-000 Boa Vista, Brazil
| | - R M de Aquino
- Departamento de Física, Universidade Federal de Roraima , 69310-000 Boa Vista, Brazil
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6
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Morell C, Tognetti V, Bignon E, Dumont E, Hernandez-Haro N, Herrera B, Grand A, Gutiérrez-Oliva S, Joubert L, Toro-Labbé A, Chermette H. Insights into the chemical meanings of the reaction electronic flux. Theor Chem Acc 2015. [DOI: 10.1007/s00214-015-1730-7] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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7
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Bodrenko IV, Della Sala F. A periodic charge-dipole electrostatic model. II. A kinetic-exchange-correlation correction. J Chem Phys 2013; 139:144109. [PMID: 24116605 DOI: 10.1063/1.4824189] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
We extend the periodic charge-dipole electrostatic model, see I. V. Bodrenko, M. Sierka, E. Fabiano, and F. Della Sala, J. Chem. Phys. 137, 134702 (2012), to include a kinetic-exchange-correlation (KXC) correction. The KXC correction is approximated by means of an extended-Hückel-type formula, it is exact in the infinite jellium model and it is also computationally efficient as it requires only the computation of overlap integrals. Tests on the linear response of silver slabs to an external electrostatic perturbation show that the KXC correction yields a very accurate description of induced dipole and of the whole induced charge density profile. We also show that the KXC parameters are quite transferable and related to the atomic polarizability.
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Affiliation(s)
- I V Bodrenko
- National Nanotechnology Laboratory (NNL), Istituto Nanoscienze-CNR, Via per Arnesano 16, 73100 Lecce, Italy
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8
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Singh RK, Tsuneda T. Reaction energetics on long-range corrected density functional theory: Diels-Alder reactions. J Comput Chem 2012; 34:379-86. [DOI: 10.1002/jcc.23145] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2012] [Revised: 08/30/2012] [Accepted: 09/05/2012] [Indexed: 11/06/2022]
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9
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Matito E, Putz MV. New link between conceptual density functional theory and electron delocalization. J Phys Chem A 2011; 115:12459-62. [PMID: 21561124 DOI: 10.1021/jp200731d] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
In this paper we give a new definition of the softness kernel based on the exchange-correlation density. This new kernel is shown to correspond to the change of electron fluctuation upon external perturbation, thus helping to bridge the gap between conceptual density functional theory and some tools describing electron localization in molecules. With the aid of a few computational calculations on diatomics we illustrate the performance of this new computational tool.
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Affiliation(s)
- Eduard Matito
- Institute of Physics, University of Szczecin, Szczecin, Poland.
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Gál T, Geerlings P, De Proft F, Torrent-Sucarrat M. A new approach to local hardness. Phys Chem Chem Phys 2011; 13:15003-15. [DOI: 10.1039/c1cp21213c] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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11
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Roy RK, Saha S. Studies of regioselectivity of large molecular systems using DFT based reactivity descriptors. ACTA ACUST UNITED AC 2010. [DOI: 10.1039/b811052m] [Citation(s) in RCA: 77] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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12
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Torrent-Sucarrat M, De Proft F, Ayers PW, Geerlings P. On the applicability of local softness and hardness. Phys Chem Chem Phys 2009; 12:1072-80. [PMID: 20094672 DOI: 10.1039/b919471a] [Citation(s) in RCA: 85] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Global hardness and softness and the associated hard/soft acid/base (HSAB) principle have been used to explain many experimental observed reactivity patterns and these concepts can be found in textbooks of general, inorganic, and organic chemistry. In addition, local versions of these reactivity indices and principles have been defined to describe the regioselectivity of systems. In a very recent article (Chem.-Eur. J. 2008, 14, 8652), the present authors have shown that the picture of these well-known descriptors is incomplete and that the understanding of these reactivity indices must be "reinterpreted". In fact, the local softness and hardness contain the same "potential information" and they should be interpreted as the "local abundance" or "concentration" of their corresponding global properties. In this contribution, we analyze the implications of this new point of view for the applicability of these well-known descriptors when comparing two sites in three situations: two sites within one molecule, two sites in two different, but noninteracting molecules, and two sites in two different, but interacting, molecules. The implications on the HSAB principle are highlighted, leading to the discussion of the role of the electrostatic interaction.
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Affiliation(s)
- M Torrent-Sucarrat
- Member of the QCMM Alliance group Ghent/Brussels, Eenheid Algemene Chemie (ALGC), Faculteit Wetenschappen, Vrije Universiteit Brussel (VUB), Pleinlaan 2, 1050 Brussels, Belgium.
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13
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Torrent-Sucarrat M, De Proft F, Geerlings P, Ayers PW. Do the local softness and hardness indicate the softest and hardest regions of a molecule? Chemistry 2008; 14:8652-60. [PMID: 18671307 DOI: 10.1002/chem.200800570] [Citation(s) in RCA: 69] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
In this work, we will show that the largest values of the local softness and hardness do not necessarily correspond to the softest and hardest regions of the molecule, respectively. Based on our results, we will argue that it is more useful to interpret the local softness and the local hardness as functions that measure the "local abundance" or "concentration" of the corresponding global properties. This new point of view helps reveal how and when these local reactivity indices are most useful.
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Affiliation(s)
- Miquel Torrent-Sucarrat
- Eenheid Algemene Chemie (ALGC), Faculteit Wetenschappen, Vrije Universiteit Brussel (VUB), Pleinlaan 2, Brussels, Belgium.
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14
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Torrent-Sucarrat M, Salvador P, Solà M, Geerlings P. The hardness kernel as the basis for global and local reactivity indices. J Comput Chem 2008; 29:1064-72. [DOI: 10.1002/jcc.20866] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
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15
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Borgoo A, Torrent-Sucarrat M, De Proft F, Geerlings P. Quantum similarity study of atoms: a bridge between hardness and similarity indices. J Chem Phys 2007; 126:234104. [PMID: 17600401 DOI: 10.1063/1.2741536] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
A hardness based similarity index for studying the quantum similarity for atoms is analyzed. The investigation of hardness and Fukui functions of atoms leads to the construction of a quantum similarity measure, which can be interpreted as a quantified comparison of chemical reactivity of atoms. Evaluation of the new measure reveals periodic tendencies throughout Mendeleev's table. Moreover on the diagonal the global hardness was recovered. Considering a corresponding quantum similarity index reveals that renormalization of the measure can mask periodic patterns. The hardness was calculated for atoms with nuclear charge 3<or=Z<or=103, using the best single configuration electron density functions available. Different hardness kernels were used and the importance of the different contributions to the kernel was investigated. The atomic self-similarities constructed in this way show a fair correlation with experimental atomic polarizability.
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Affiliation(s)
- A Borgoo
- Department of General Chemistry (ALGC), Vrije Universiteit Brussel (VUB, Free University of Brussels), Pleinlaan 2, 1050 Brussels, Belgium
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16
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Gázquez JL, Garza J, Hinojosa FD, Vela A. Chemical hardness and the discontinuity of the Kohn-Sham exchange-correlation potential. J Chem Phys 2007; 126:214105. [PMID: 17567188 DOI: 10.1063/1.2741529] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Chemical hardness, identified as the difference between the vertical first ionization potential I and the vertical electron affinity A, is analyzed in the context of the ionization theorems to derive expressions for its evaluation at different levels of approximation that arise as a direct consequence of the derivative discontinuity of the exchange-correlation potential. The quantities involved in these expressions incorporate indirectly the effects of the discontinuity, but their values may be calculated with any functional of the local density approximation, generalized gradient approximation, or optimized effective potential type, with or without derivative discontinuity, and with or without the correct asymptotic behavior. By comparison with the vertical energy difference values of I and A, which requires the calculation of the N-, (N-1)-, and (N+1)-electron systems, it is found, for a set of 14 closed shell molecules, that the difference between the eigenvalues of the highest occupied molecular orbitals of the N- and (N+1)-electron systems leads to rather accurate values, when the correct asymptotic behavior is incorporated, and that a second-order one-body perturbation approach that only requires information from the N-electron system leads to reasonable values.
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Affiliation(s)
- José L Gázquez
- Departamento de Química, División de Ciencias Básicas e Ingeniería, Universidad Autónoma Metropolitana-Iztapalapa, A. P. 55-534, Mexico, Distrito Federal 09340, Mexico
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17
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Torrent-Sucarrat M, Geerlings P. Analogies and differences between two ways to evaluate the global hardness. J Chem Phys 2006; 125:244101. [PMID: 17199334 DOI: 10.1063/1.2406072] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
The weight of the energetic components (electronic kinetic, electron-nucleus and electron-electron Coulombic, and correlation energies) of the ionization potential, electron affinity, chemical potential, and global hardness is evaluated and contrasted with the energetic components of the hardness kernel and the experimental values of these properties for 40 systems. The contrast of the hardness terms obtained from finite difference and hardness kernel gives some insight on the possible implications to differentiate the electronic energy with respect to the number electrons or the electron density.
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Affiliation(s)
- Miquel Torrent-Sucarrat
- Eenheid Algemene Chemie, Faculteit Wetenschappen, Vrije Universiteit Brussel (VUB), Pleinlaan 2, B-1050 Brussels, Belgium.
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18
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Torrent-Sucarrat M, Salvador P, Geerlings P, Solà M. On the quality of the hardness kernel and the Fukui function to evaluate the global hardness. J Comput Chem 2006; 28:574-83. [PMID: 17186480 DOI: 10.1002/jcc.20535] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
An approximated hardness kernel, which includes the second derivative with respect to the density of the kinetic energy, the electron-electron coulomb repulsion, and the exchange density functionals, has been tested for the calculation of the global hardness. The results obtained for a series of 40 cations and neutral systems and 16 anions represent in most cases an improvement of the results obtained using the HOMO-LUMO gap approach and indicate the viability of this approach to evaluate global hardness. In addition, the relevance of the Fukui function approximation and the role of the three components of the hardness kernel in the evaluation of the global hardness have been analyzed.
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Affiliation(s)
- Miquel Torrent-Sucarrat
- Eenheid Algemene Chemie, Faculteit Wetenschappen, Vrije Universiteit Brussel, Pleinlaan 2, Brussels, Belgium.
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19
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Torrent-Sucarrat M, Luis JM, Duran M, Solà M. An assessment of a simple hardness kernel approximation for the calculation of the global hardness in a series of Lewis acids and bases. ACTA ACUST UNITED AC 2005. [DOI: 10.1016/j.theochem.2005.02.018] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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20
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Beck ME. Do Fukui Function Maxima Relate to Sites of Metabolism? A Critical Case Study. J Chem Inf Model 2005; 45:273-82. [PMID: 15807488 DOI: 10.1021/ci049687n] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The usefulness of local reactivity descriptors for understanding drug metabolism is investigated. Electrophilic Fukui functions are calculated for 18 drugs and 11 agrochemicals and their relation to experimentally observed metabolites is discussed. Maxima of the Fukui functions correspond to major sites of metabolic attack in many examples, facilitating a posteriori understanding of experimental findings. In the second part of the paper, the nature of the electrophilic oxidant species in cytochromes, called "Compound I" (Cpd I), is investigated within the Fukui framework. Nucleophilic Fukui functions are calculated involving the relevant spin states of Cpd I, allowing a more qualitative, intuitive understanding of its reactivity.
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Affiliation(s)
- Michael E Beck
- Bayer CropScience, Research/Scientific Computing, Agricultural Centre Monheim, D-40789 Monheim, Germany.
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21
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Torrent-Sucarrat M, Duran M, Luis JM, Solà M. Generalizing the Breakdown of the Maximum Hardness and Minimum Polarizabilities Principles for Nontotally Symmetric Vibrations to Non-π-Conjugated Organic Molecules. J Phys Chem A 2005; 109:615-21. [PMID: 16833387 DOI: 10.1021/jp0470804] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
In previous works we have shown that certain pi-conjugated organic molecules possess nontotally symmetric vibrations that break the maximum hardness (MHP) and minimum polarizability principles (MPP). We have also derived a set of simple rules to determine a priori without calculations whether a particular pi-conjugated organic molecule violates these two principles. In the present work, we generalize these results, and we show that not only pi-conjugated organic molecules but also other molecules without pi-conjugated structure or even pi-bonds can exhibit nontotally symmetric molecular distortions that do not follow these two principles. We have also found that the breakdowns of the MHP and the MPP are not necessarily connected, since the polarizability is not always proportional to the softness. Finally, we also introduced a methodology based on the diagonalization of the hardness Hessian matrix with respect to the vibrational normal coordinates to determine the nontotally symmetric molecular displacements that do not follow the MHP.
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Affiliation(s)
- Miquel Torrent-Sucarrat
- Institut de Química Computacional and Departament de Química, Universitat de Girona, E-17071 Girona, Catalonia, Spain
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22
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Torrent-Sucarrat M, Luis JM, Duran M, Sola M. The hardness profile as a tool to detect spurious stationary points in the potential energy surface. J Chem Phys 2004; 120:10914-24. [PMID: 15268121 DOI: 10.1063/1.1742793] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
In the present work, we have computed the energy and hardness profiles for a series of inter and intramolecular conformational changes at several levels of calculation. All processes studied have in common the fact that the choice of a weak methodology or a poor basis set results in the presence of spurious stationary points in the energy profile. At variance with the energy profiles, the hardness profiles calculated as the difference between the vertical ionization potential and electron affinity always show the correct number of stationary points independently of the basis set and methodology used. For this reason, we have concluded that hardness profiles can be used to check the reliability of the energy profiles for those chemical systems that, because of their size, cannot be treated with high level ab initio methods.
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Affiliation(s)
- Miquel Torrent-Sucarrat
- Institut de Química Computacional and Departament de Química, Universitat de Girona, E-17071 Girona, Catalonia, Spain
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23
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Putz MV, Russo N, Sicilia E. On the applicability of the HSAB principle through the use of improved computational schemes for chemical hardness evaluation. J Comput Chem 2004; 25:994-1003. [PMID: 15027111 DOI: 10.1002/jcc.20027] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Finite difference schemes, named Compact Finite Difference Schemes with Spectral-like Resolution, have been used for a less crude approximation of the analytical hardness definition as the second-order derivative of the energy with respect to the electron number. The improved computational schemes, at different levels of theory, have been used to calculate global hardness values of some probe bases, traditionally classified as hard and soft on the basis of their chemical behavior, and to investigate the quantitative applicability of the HSAB principle. Exchange acid-base reactions have been used to test the HSAB principle assuming the reaction energies as a measure of the stabilization of product adducts.
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Affiliation(s)
- Mihai V Putz
- Dipartimento di Chimica and Centro di Calcolo ad Alte Prestazioni per Elaborazioni Parallele e Distribuite-Centro d'Eccellenza MURST, Università della Calabria, I-87030 Arcavacata di Rende, Italy
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24
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Affiliation(s)
- P Geerlings
- Eenheid Algemene Chemie, Faculteit Wetenschappen, Vrije Universiteit Brussel, Pleinlaan 2, 1050 Brussels, Belgium.
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