1
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Guerra C, Ayarde-Henríquez L, Duque-Noreña M, Cárdenas C, Pérez P, Chamorro E. On the nature of bonding in the photochemical addition of two ethylenes: C-C bond formation in the excited state? Phys Chem Chem Phys 2021; 23:20598-20606. [PMID: 34505860 DOI: 10.1039/d1cp03554a] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
In this work, the 2s + 2s (face-to-face) prototypical example of a photochemical reaction has been re-examined to characterize the evolution of chemical bonding. The analysis of the electron localization function (as an indirect measure of the Pauli principle) along the minimum energy path provides strong evidence supporting that CC bond formation occurs not in the excited state but in the ground electronic state after crossing the rhombohedral S1/S0 conical intersection.
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Affiliation(s)
- Cristian Guerra
- Universidad Andres Bello, Facultad de Ciencias Exactas, Departamento de Ciencias Químicas, Avenida República 275, 8370146, Santiago, Chile.
| | - Leandro Ayarde-Henríquez
- Universidad Andres Bello, Facultad de Ciencias Exactas, Departamento de Ciencias Químicas, Avenida República 275, 8370146, Santiago, Chile.
| | - Mario Duque-Noreña
- Universidad Andres Bello, Facultad de Ciencias Exactas, Departamento de Ciencias Químicas, Avenida República 275, 8370146, Santiago, Chile.
| | - Carlos Cárdenas
- Universidad de Chile, Facultad de Ciencias, Departamento de Física, Avenida Las Palmeras 3425, Santiago, Chile. .,Centro para el Desarrollo de la Nanociencia y la Nanotecnología (CEDENNA), 9170124 Santiago, Chile
| | - Patricia Pérez
- Universidad Andres Bello, Facultad de Ciencias Exactas, Departamento de Ciencias Químicas, Avenida República 275, 8370146, Santiago, Chile.
| | - Eduardo Chamorro
- Universidad Andres Bello, Facultad de Ciencias Exactas, Departamento de Ciencias Químicas, Avenida República 275, 8370146, Santiago, Chile.
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2
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Mohammad-Salim HA, Abdallah HH, Maiyelvaganan KR, Prakash M, Hochlaf M. Mechanistic study of the [2+2] cycloaddition reaction of cyclohexenone and its derivatives with vinyl acetate. Theor Chem Acc 2020. [DOI: 10.1007/s00214-019-2542-y] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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3
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Tashiro K, Yamamoto H, Sugimoto K, Takahama T, Tanaka M, Hasegawa M. Experimental Determination of the Geometrical Relation between Monomer and Polymer Species of 2,5-Distyrylpyrazine Single Crystal in the Topotactic Photoinduced Polymerization Reaction. Macromolecules 2019. [DOI: 10.1021/acs.macromol.9b00031] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Kohji Tashiro
- Graduate School of Engineering, Toyota Technological Institute, Tempaku, Nagoya 468-8511, Japan
| | - Hiroko Yamamoto
- Aichi Synchrot1ron Radiation Center, Aichi Science and Technology Foundation, 250-3
Minamiyamaguchi, Seto 489-0965, Japan
| | - Kunihisa Sugimoto
- Japan Synchrotron Radiation Research Institute, SPring-8, Kouto 1-1-1, Sayo 679-5198, Japan
| | - Tomohiko Takahama
- Graduate School of Engineering, Toyota Technological Institute, Tempaku, Nagoya 468-8511, Japan
| | - Masaya Tanaka
- Graduate School of Engineering, Toyota Technological Institute, Tempaku, Nagoya 468-8511, Japan
| | - Masaki Hasegawa
- Department of Synthetic Chemistry, Faculty of Engineering, University of Tokyo, Hongo, Bunkyo-ku, Tokyo, Japan
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4
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Badran I, Rauk A, Shi Y. New Orbital Symmetry-Allowed Route for Cycloreversion of Silacyclobutane and Its Methyl Derivatives. J Phys Chem A 2019; 123:1749-1757. [DOI: 10.1021/acs.jpca.8b08071] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Affiliation(s)
- Ismail Badran
- Department of Chemistry, University of Calgary, Calgary, Alberta T2N 1N4, Canada
| | - Arvi Rauk
- Department of Chemistry, University of Calgary, Calgary, Alberta T2N 1N4, Canada
| | - Yujun Shi
- Department of Chemistry, University of Calgary, Calgary, Alberta T2N 1N4, Canada
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5
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Ghosh S, Verma P, Cramer CJ, Gagliardi L, Truhlar DG. Combining Wave Function Methods with Density Functional Theory for Excited States. Chem Rev 2018; 118:7249-7292. [PMID: 30044618 DOI: 10.1021/acs.chemrev.8b00193] [Citation(s) in RCA: 135] [Impact Index Per Article: 22.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
We review state-of-the-art electronic structure methods based both on wave function theory (WFT) and density functional theory (DFT). Strengths and limitations of both the wave function and density functional based approaches are discussed, and modern attempts to combine these two methods are presented. The challenges in modeling excited-state chemistry using both single-reference and multireference methods are described. Topics covered include background, combining density functional theory with single-configuration wave function theory, generalized Kohn-Sham (KS) theory, global hybrids, range-separated hybrids, local hybrids, using KS orbitals in many-body theory (including calculations of the self-energy and the GW approximation), Bethe-Salpeter equation, algorithms to accelerate GW calculations, combining DFT with multiconfigurational WFT, orbital-dependent correlation functionals based on multiconfigurational WFT, building multiconfigurational wave functions from KS configurations, adding correlation functionals to multiconfiguration self-consistent-field (MCSCF) energies, combining DFT with configuration-interaction singles by means of time-dependent DFT, using range separation to combine DFT with MCSCF, embedding multiconfigurational WFT in DFT, and multiconfiguration pair-density functional theory.
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Affiliation(s)
- Soumen Ghosh
- Department of Chemistry, Chemical Theory Center, and Minnesota Supercomputing Institute , University of Minnesota , 207 Pleasant Street SE , Minneapolis , Minnesota 55455-0431 , United States
| | - Pragya Verma
- Department of Chemistry, Chemical Theory Center, and Minnesota Supercomputing Institute , University of Minnesota , 207 Pleasant Street SE , Minneapolis , Minnesota 55455-0431 , United States
| | - Christopher J Cramer
- Department of Chemistry, Chemical Theory Center, and Minnesota Supercomputing Institute , University of Minnesota , 207 Pleasant Street SE , Minneapolis , Minnesota 55455-0431 , United States
| | - Laura Gagliardi
- Department of Chemistry, Chemical Theory Center, and Minnesota Supercomputing Institute , University of Minnesota , 207 Pleasant Street SE , Minneapolis , Minnesota 55455-0431 , United States
| | - Donald G Truhlar
- Department of Chemistry, Chemical Theory Center, and Minnesota Supercomputing Institute , University of Minnesota , 207 Pleasant Street SE , Minneapolis , Minnesota 55455-0431 , United States
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6
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7
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Peterson PW, Shevchenko N, Breiner B, Manoharan M, Lufti F, Delaune J, Kingsley M, Kovnir K, Alabugin IV. Orbital Crossings Activated through Electron Injection: Opening Communication between Orthogonal Orbitals in Anionic C1–C5 Cyclizations of Enediynes. J Am Chem Soc 2016; 138:15617-15628. [DOI: 10.1021/jacs.6b08540] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Affiliation(s)
- Paul W. Peterson
- Department of Chemistry and
Biochemistry, Florida State University, 95 Chieftain Way, Tallahassee, Florida 32301, United States
| | - Nikolay Shevchenko
- Department of Chemistry and
Biochemistry, Florida State University, 95 Chieftain Way, Tallahassee, Florida 32301, United States
| | - Boris Breiner
- Department of Chemistry and
Biochemistry, Florida State University, 95 Chieftain Way, Tallahassee, Florida 32301, United States
| | - Mariappan Manoharan
- Department of Chemistry and
Biochemistry, Florida State University, 95 Chieftain Way, Tallahassee, Florida 32301, United States
| | - Forat Lufti
- Department of Chemistry and
Biochemistry, Florida State University, 95 Chieftain Way, Tallahassee, Florida 32301, United States
| | - Jess Delaune
- Department of Chemistry and
Biochemistry, Florida State University, 95 Chieftain Way, Tallahassee, Florida 32301, United States
| | - Margaret Kingsley
- Department of Chemistry and
Biochemistry, Florida State University, 95 Chieftain Way, Tallahassee, Florida 32301, United States
| | - Kirill Kovnir
- Department of Chemistry and
Biochemistry, Florida State University, 95 Chieftain Way, Tallahassee, Florida 32301, United States
| | - Igor V. Alabugin
- Department of Chemistry and
Biochemistry, Florida State University, 95 Chieftain Way, Tallahassee, Florida 32301, United States
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8
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Franzen S, Skalski B, Bartolotti L, Delley B. The coupling of tautomerization to hydration in the transition state on the pyrimidine photohydration reaction path. Phys Chem Chem Phys 2014; 16:20164-74. [DOI: 10.1039/c4cp02160f] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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9
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Nikolaev VA, Supurgibekov MB, Haiges R, Linden A, Prakash GS. Thermolysis of trifluoromethyl-containing vinyldiazocarbonyl compounds and X-ray crystal structure analysis of unexpected reaction products. J Fluor Chem 2013. [DOI: 10.1016/j.jfluchem.2013.07.019] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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10
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Antal Z, Warburton PL, Mezey PG. Electron density shape analysis of a family of through-space and through-bond interactions. Phys Chem Chem Phys 2013; 16:918-32. [PMID: 24276369 DOI: 10.1039/c3cp53954g] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A family of styrene derivatives has been used to study the effects of through-space and through-bond interactions on the local and global shapes of electron densities of complete molecules and a set of substituents on their central rings. Shape analysis methods which have been used extensively in the past for the study of molecular property-molecular shape correlations have shown that in these molecules a complementary role is played by the through-space and through-bond interactions. For each specific example, the dominance of either one of the two interactions can be identified and interpreted in terms of local shapes and the typical reactivities of the various substituents. Three levels of quantum chemical computational methods have been applied for these structures, including the B3LYP/cc-pVTZ level of density functional methodology, and the essential conclusions are the same for all three levels. The general approach is suggested as a tool for the identification of specific interaction types which are able to modify molecular electron densities. By separately influencing the through-space and through-bond components using polar groups and groups capable of conjugation, some fine-tuning of the overall effects becomes possible. The method described may contribute to an improved understanding and control of molecular properties involving complex interactions with a possible role in the emerging field of molecular design.
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Affiliation(s)
- Zoltan Antal
- Scientific Modeling and Simulation Laboratory (SMSL), Department of Chemistry and Department of Physics and Physical Oceanography, Memorial University of Newfoundland and Labrador, St. John's, Newfoundland A1B3X7, Canada.
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11
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Shiroudi A, Zahedi E. DFT Calculations of the Elimination Kinetics of Silacyclobutanes and its Methyl Derivatives in the Gas-Phase. PHOSPHORUS SULFUR 2012. [DOI: 10.1080/10426507.2011.636111] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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12
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Kinzel D, Stolle A, Ondruschka B, González L. Quantum chemical investigation of the thermal rearrangement of cis- and trans-pinane. Phys Chem Chem Phys 2010; 12:9884-92. [PMID: 20532363 DOI: 10.1039/c001019g] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The thermal rearrangement reactions of cis-pinane, 1, and trans-pinane, 2, into beta-citronellene, 3, and isocitronellene, 4, have been investigated using ab initio multiconfigurational CASSCF and CASSCF MP2 calculations. Concerted as well as stepwise retro-[2+2]-cycloaddition conversion mechanisms are discussed and the corresponding stationary points along the relevant reaction paths from the bicyclic starting compounds into their acyclic isomers have been optimized. Our calculations show that the stepwise retro-[2+2]-cycloaddition via biradicals is energetically favoured with respect to the concerted mechanism. In the biradical pathways to 3 and 4, it was found that a gauche ring opening of the cyclobutane ring in 1 and 2, respectively, shows significantly lower activation barriers than the competing anti ring opening. With the predicted reaction paths, the calculated activation energies are in very good agreement with experimental values. The reaction mechanisms can explain the differences in the reactivity of 1 and 2, as well as the selectivity differences with respect to the formation of 3 and 4, reported in previous kinetic studies.
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Affiliation(s)
- Daniel Kinzel
- Institute for Physical Chemistry, Friedrich-Schiller University Jena, Helmholtzweg 4, D-07743 Jena, Germany
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13
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Mandado M, Ponec R. Electron reorganization in allowed and forbidden pericyclic reactions: multicenter bond indices as a measure of aromaticity and/or anti-aromaticity in transition states of pericyclic electrocyclizations. J PHYS ORG CHEM 2009. [DOI: 10.1002/poc.1589] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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14
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Wu Y, Xue Y, Kim CK. Computational studies on the dimers and the thermal dimerization of norbornadiene. J Comput Chem 2008; 29:1250-8. [PMID: 18074342 DOI: 10.1002/jcc.20887] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
In this study, 14 norbornadiene (NBD) dimers and the thermal dimerization mechanism were studied using the hybrid density functional theory (B3LYP) and the second-order multiconfigurational perturbation theory (CASPT2). In the process of dimerization, the biradical stationary points were located using the unrestricted, broken-spin, symmetry approach. The pathways were divided into eight parts to aid the analysis of their mechanisms. Our results indicated that the process for the formation of the cage-like heptacyclo[6.6.0.0.260.3130.411059.01014] tetradecane (HCTD, D14) is highly exothermic (92.15 kcal/mol), indicating that D14 is the most stable NBD dimer. However, the formation of D14 is very difficult to achieve kinetically because of a higher barrier in the thermal dimerization. On the contrary, the formation of exo-cis-exo (D5) is kinetically favorable, but thermodynamically unfavorable at higher temperature. Therefore, the combination of both thermodynamic and kinetic factors indicated that the formation of exo-exo (D9), which resembles the product of the pseudo-Diels-Alder addition, is most likely in the NBD dimerization.
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Affiliation(s)
- Yong Wu
- Department of Chemistry, Inha University, Incheon 402-751, Korea
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15
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Zhang RB, Eriksson LA. A triplet mechanism for the formation of cyclobutane pyrimidine dimers in UV-irradiated DNA. J Phys Chem B 2007; 110:7556-62. [PMID: 16599537 DOI: 10.1021/jp060196a] [Citation(s) in RCA: 58] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The reaction pathways for the photochemical formation of cyclobutane thymine dimers in DNA are explored using hybrid density functional theory techniques. It is concluded that the thymine-thymine [2 + 2] cycloaddition displays favorable energy barriers and reaction energies in both the triplet and the singlet excited states. The stepwise cycloaddition in the triplet excited state involves the initial formation of a diradical followed by ring closure via singlet-triplet interaction. The triplet mechanism is thus completely different from the concerted singlet state cycloaddition processes. The key geometric features and electron spin densities are also discussed. Bulk solvation has a major effect by reducing the barriers and increasing the diradical stabilities. The present results provide a rationale for the faster cycloreaction observed in the singlet excited states than in the triplet excited states.
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Affiliation(s)
- Ru Bo Zhang
- Department of Natural Sciences and Orebro Life Science Center, Orebro University, 70182 Orebro, Sweden
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16
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Durbeej B, Eriksson LA. On the Formation of Cyclobutane Pyrimidine Dimers in UV-irradiated DNA: Why are Thymines More Reactive?¶. Photochem Photobiol 2007. [DOI: 10.1562/0031-8655(2003)0780159otfocp2.0.co2] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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17
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Levine BG, Ko C, Quenneville J, MartÍnez TJ. Conical intersections and double excitations in time-dependent density functional theory. Mol Phys 2007. [DOI: 10.1080/00268970500417762] [Citation(s) in RCA: 402] [Impact Index Per Article: 23.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Affiliation(s)
- Benjamin G. Levine
- a Department of Chemistry , The Beckman Institute, and The F. Seitz Materials Research Laboratory, University of Illinois at Urbana-Champaign , Urbana, IL 61801, USA
| | - Chaehyuk Ko
- a Department of Chemistry , The Beckman Institute, and The F. Seitz Materials Research Laboratory, University of Illinois at Urbana-Champaign , Urbana, IL 61801, USA
| | - Jason Quenneville
- a Department of Chemistry , The Beckman Institute, and The F. Seitz Materials Research Laboratory, University of Illinois at Urbana-Champaign , Urbana, IL 61801, USA
| | - Todd J. MartÍnez
- a Department of Chemistry , The Beckman Institute, and The F. Seitz Materials Research Laboratory, University of Illinois at Urbana-Champaign , Urbana, IL 61801, USA
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18
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Avenoza A, Busto JH, Canal N, García JI, Jiménez-Osés G, Peregrina JM, Pérez-Fernández M. Mechanistic study of the ring-size modulation in Michael–Dieckmann type reactions of 2-acylaminoacrylates with ketene diethyl acetal. NEW J CHEM 2007. [DOI: 10.1039/b615220a] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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19
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Ribas-Ariño J, Curioni A, Andreoni W, Novoa JJ. Broken inter-C60 bonds as the cause of magnetism in polymeric C60: a density functional study using C60 dimers. J Phys Chem A 2005; 109:4979-82. [PMID: 16833847 DOI: 10.1021/jp050753d] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Bond breaking in C60-C60 dimeric units is believed to play an important role in the onset of magnetism in 2D polymeric C60. On the basis of density-functional theory, the calculations we present here provide further insight into this mechanism through a quantitative characterization of the bond-breaking processes in the isolated dumbbell-shaped C60 dimer. In particular, the analysis of the calculated potential energy surfaces for the low-lying singlet and triplet states identifies and locates the S0-T2 crossing point, which is crucial for the transition to a magnetic state to take place under thermal conditions. These results also suggest a possible new approach to the production of magnetic polymeric C60.
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20
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Braña P, Gimeno J, Sordo JA. Unusual Intramolecular [2 + 2] Cycloaddition of Allyl and Vinylidene CC Bonds under Mild Conditions: A Theoretical Analysis. J Org Chem 2004; 69:2544-50. [PMID: 15049656 DOI: 10.1021/jo035346h] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
A theoretical analysis allows for the rationalization of the recently reported unusual formation under mild conditions of a cyclobutylidene ring from a diastereoselective [2 + 2] intramolecular cycloaddition of two C=C systems. The reaction takes place by heating in dichloromethane the vinylidene complexes [Ru((eta(5),eta(3)-C(9)H(7))[=C=C(R)H][kappa(1)-(P)-PPh(2)(C(3)H(5))](PPh(3))][BF(4)] (R = Ph, p-Me-C(6)H(4)) (1) yielding the bicyclic alkylidene complexes [Ru((eta(5),eta(3)-C(9)H(7))[kappa(2)-(P,C)-(=CC(R)HCH(2)CHCH(2)-PPh(2)](PPh(3))][BF(4)] (2). The proposed mechanism represents an alternative to the classical Woodward-Hoffmann's supra-antara approach.
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Affiliation(s)
- Pedro Braña
- Laboratorio de Química Computacional, Instituto de Química Organometálica Enrique Moles (Unidad asociada al CSIC), Facultad de Química, Universidad de Oviedo, Julián Clavería 8, 33006, Oviedo, Principado de Asturias, Spain
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21
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Aktah D, Passerone D, Parrinello M. Insights into the Electronic Dynamics in Chemical Reactions. J Phys Chem A 2004. [DOI: 10.1021/jp036572y] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Daniel Aktah
- CSCS−Swiss Center for Scientific Computing, Via Cantonale, 6928 Manno, Switzerland, and Department of Physical Chemistry, Swiss Federal Institute of Technology (ETH), Hönggerberg HCI, 8093 Zurich, Switzerland
| | - Daniele Passerone
- CSCS−Swiss Center for Scientific Computing, Via Cantonale, 6928 Manno, Switzerland, and Department of Physical Chemistry, Swiss Federal Institute of Technology (ETH), Hönggerberg HCI, 8093 Zurich, Switzerland
| | - Michele Parrinello
- CSCS−Swiss Center for Scientific Computing, Via Cantonale, 6928 Manno, Switzerland, and Department of Physical Chemistry, Swiss Federal Institute of Technology (ETH), Hönggerberg HCI, 8093 Zurich, Switzerland
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22
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Gusel'nikov LE. Hetero-π-systems from 2+2 cycloreversions. Part 1. Gusel'nikov–Flowers route to silenes and origination of the chemistry of doubly bonded silicon. Coord Chem Rev 2003. [DOI: 10.1016/s0010-8545(03)00104-8] [Citation(s) in RCA: 59] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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23
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Durbeej B, Eriksson LA. On the formation of cyclobutane pyrimidine dimers in UV-irradiated DNA: why are thymines more reactive? Photochem Photobiol 2003; 78:159-67. [PMID: 12945584 DOI: 10.1562/0031-8655(2003)078<0159:otfocp>2.0.co;2] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
The reaction pathways for thermal and photochemical formation of cyclobutane pyrimidine dimers in DNA are explored using density functional theory techniques. Although it is found that the thermal [2 + 2] cycloadditions of thymine + thymine (T + T --> T x T), cytosine + cytosine (C + C --> C x C) and cytosine + thymine (C + T --> C x T) all are similarly unfavorable in terms of energy barriers and reaction energies, the excited-state energy curves associated with the corresponding photochemical cycloadditions display differences that--in line with experimental findings--unanimously point to the predominance of T x T in UV-irradiated DNA. It is shown that the photocycloaddition of thymines is facilitated by the fact that the S1 state of the corresponding reactant complex lies comparatively high in energy. Moreover, at a nuclear configuration coinciding with the ground-state transition structure, the excited-state energy curve displays an absolute minimum only for the T + T system. Finally, the T + T system is also associated with the most favorable excited-state energy barriers and has the smallest S2-S0 energy gap at the ground-state transition structure.
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Affiliation(s)
- Bo Durbeej
- Department of Quantum Chemistry, Uppsala University, Uppsala, Sweden
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24
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Calvo-Losada S, Enríquez F, Martín-Ortiz J, Quirante JJ. Thermal Fragmentation of 3-Vinyloxetane: A Quantum Chemical Study. J Phys Chem A 2003. [DOI: 10.1021/jp022373n] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- S. Calvo-Losada
- Departamento de Química Física, Facultad de Ciencias, Universidad de Málaga, Campus de Teatinos s/n, 29071 Málaga, Spain
| | - F. Enríquez
- Departamento de Química Física, Facultad de Ciencias, Universidad de Málaga, Campus de Teatinos s/n, 29071 Málaga, Spain
| | - J. Martín-Ortiz
- Departamento de Química Física, Facultad de Ciencias, Universidad de Málaga, Campus de Teatinos s/n, 29071 Málaga, Spain
| | - J. J. Quirante
- Departamento de Química Física, Facultad de Ciencias, Universidad de Málaga, Campus de Teatinos s/n, 29071 Málaga, Spain
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Venturini A, González J. A CASPT2 and CASSCF approach to the cycloaddition of ketene and imine: a new mechanistic scheme of the Staudinger reaction. J Org Chem 2002; 67:9089-92. [PMID: 12467436 DOI: 10.1021/jo026188h] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
We report a new theoretical study of the mechanism of the parent Staudinger reaction between ketene and formaldimine. This mechanism, in contrast with previously reported computational studies, involves the formation of two different intermediates, gauche and trans, which can be interconnected on the potential energy surface depending upon reaction conditions. This novel CASPT2/CASSCF mechanistic scheme may be considered a new starting point to rationalize stereochemical outcome and solvent effects in these reactions.
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Affiliation(s)
- Alessandro Venturini
- C.N.R.-Istituto dei Composti del Carbonio contenenti Eteroatomi e loro Applicazioni, Via Gobetti 101, 40129 Bologna, Italy.
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Gusel'nikov LE, Avakyan VG, Guselnikov SL. Effect of geminal substitution at silicon on 1-sila- and 1,3-disilacyclobutanes' strain energies, their 2+2 cycloreversion enthalpies, and Si=C pi-bond energies in silenes. J Am Chem Soc 2002; 124:662-71. [PMID: 11804497 DOI: 10.1021/ja011287i] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
To evaluate the effect of geminal substitution at silicon on 1-sila- and 1,3-disilacyclobutanes' strain energies, their 2+2 cycloreversion enthalpies, and Si=C pi-bond energies in silenes, an ab initio MO study of silenes, R2Si=CH2 (1), 1-silacyclobutanes, cyclo-R2Si(CH2)3 (2), and 1,3-disilacyclobutanes, cyclo-(R2SiCH2)2 (3), was performed using the level of theory denoted MP4/TZ(d)//MP2/6-31G(d) (TZ means the 6-311G(d) basis set for elements of the second period and hydrogen, and the McLean-Chandler (12s,9p)/[6s,5p](d) basis set for the third period elements). In the series R = H, CH3, SiH3, CH3O, NH2, Cl, F, the growth of the reaction enthalpies and strain energies is proportional to the substituents' electronegativities. 2+2 cycloreversion of 2 is endothermic by 40.6-63.1 kcal/mol, whereas that of 3 is endothermic by 72.7-114.2 kcal/mol. On going from a silicon to a fluorine substituent at the sp2-hybridized silicon atom, the pi-bond energy in 1 weakens by 11.3 kcal/mol, and the Si=C bond length shortens by 0.053 A. The effect of substituents' electronegativities at the double-bonded silicon atom in silenes is formulated as follows: the higher electronegativity, the shorter and the weaker the Si=C pi-bond. The latter is rationalized in terms of more strained geometry resulting from the energetic cost for planarizing the R2SiC moiety. The enthalpies of the ring-opening reaction are 68.0-80.1 kcal/mol (a cleavage of the Si-C bond in 3), 65.0-76.4 kcal/mol (a cleavage of the Si-C bond in 2), and 58.0-64.9 kcal/mol (a cleavage of the C-C bond in 2). The pronounced difference in the enthalpies of 2+2 cycloreversion of 1-sila- and 1,3-disilacyclobutanes is mainly due to the difference in the enthalpies of diradicals' decomposition. The decomposition of diradicals resulting from a cleavage of C-C and Si-C bonds in 2 is exothermic by 24.3-3.3 kcal/mol (apart from the difluoro derivative which is endothermic by 5.1 kcal/mol) and 27.0-13.3 kcal/mol, respectively. The decomposition of a 1,4-diradical resulting from ring opening of 3, apart from the disilyl derivative, is the endothermic process for which the enthalpy varies from 10.6 to 40.4 kcal/mol.
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Affiliation(s)
- Leonid E Gusel'nikov
- Topchiev Institute of Petrochemical Synthesis, Russian Academy of Sciences, 29 Leninsky Prospect, 119991 GSP-1, Moscow, Russia.
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Morkin TL, Leigh WJ. Arrhenius Parameters for the Head-to-Tail Dimerizations of 1,1-Diphenylsilene and 1,1-Diphenylgermene in Solution. Organometallics 2001. [DOI: 10.1021/om0103409] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Tracy L. Morkin
- Department of Chemistry, McMaster University, 1280 Main Street West, Hamilton, Ontario, Canada L8S 4M1
| | - William J. Leigh
- Department of Chemistry, McMaster University, 1280 Main Street West, Hamilton, Ontario, Canada L8S 4M1
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Morkin TL, Leigh WJ. Substituent effects on the reactivity of the silicon-carbon double bond. Acc Chem Res 2001; 34:129-36. [PMID: 11263871 DOI: 10.1021/ar960252y] [Citation(s) in RCA: 93] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Laser flash photolysis of various organosilicon compounds such as aryl-, vinyl-, and alkynyldisilanes, silacyclobutanes and silacyclobutenes, and alpha-silylketenes and -diazomethanes leads to the formation of reactive silenes which can be detected directly in solution, allowing detailed studies of the kinetics and mechanisms of their reactions with nucleophiles. Over 30 transient silenes have now been studied by these methods, providing the opportunity to systematically assess the effects of substituents at silicon and carbon on the reactivity of the Si=C bond.
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Affiliation(s)
- T L Morkin
- Department of Chemistry, McMaster University, Hamilton, Ontario Canada L8S 4M1
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Escudié J, Ranaivonjatovo H, Rigon L. Heavy allenes and cumulenes e=c=e' and e=c=c=e' (e = p, as, si, ge, sn; e' = C, N, p, as, o, s). Chem Rev 2000; 100:3639-96. [PMID: 11749324 DOI: 10.1021/cr990013z] [Citation(s) in RCA: 119] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- J Escudié
- Hétérochimie Fondamentale et Appliquée, UMR 5069, Université Paul Sabatier, 118 route de Narbonne, 31062 Toulouse 04, France
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Computational explorations of vinylcyclopropane-cyclopentene rearrangements and competing diradical stereoisomerizations. J Org Chem 2000; 65:3259-68. [PMID: 10843604 DOI: 10.1021/jo991026f] [Citation(s) in RCA: 43] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The rearrangements and stereoisomerizations of four systems, vinylcyclopropane, 4-tert-butylvinylcyclopropane, 5-methylvinylcyclopropane, and 2,5-dimethylvinylcyclopropane, as well as a variety of deuterated derivatives and 1- and 2-methyl-, methoxy-, difluoro-, and amino-substituted species, were studied by density functional theory calculations using the B3LYP functional and the 6-31G basis set. Energies were evaluated with CASSCF(4, 4)/6-31G single point calculations. The major product is obtained by the si pathway. Structures on this path are essentially pure diradical in character. Higher energy diradical species and intermediates are responsible for the scrambling of the stereochemistry. The stereoselectivity of the reaction is increased by substituents which increase the relative energy of the species involved in competing stereoselectivities. The computed secondary kinetic isotope effects reproduce the experimental values reported in the literature.
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31
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Ben-Nun M, Quenneville J, Martínez TJ. Ab Initio Multiple Spawning: Photochemistry from First Principles Quantum Molecular Dynamics. J Phys Chem A 2000. [DOI: 10.1021/jp994174i] [Citation(s) in RCA: 644] [Impact Index Per Article: 26.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- M. Ben-Nun
- Department of Chemistry and The Beckman Institute, University of Illinois, Urbana, Illinois 61801
| | - Jason Quenneville
- Department of Chemistry and The Beckman Institute, University of Illinois, Urbana, Illinois 61801
| | - Todd J. Martínez
- Department of Chemistry and The Beckman Institute, University of Illinois, Urbana, Illinois 61801
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32
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Baer M, Varandas AJC, Englman R. Topological effects due to conical intersections: A model study of two interacting conical intersections. J Chem Phys 1999. [DOI: 10.1063/1.480280] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023] Open
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33
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Toltl NP, Stradiotto M, Morkin TL, Leigh WJ. Homo- and Cross-[2+2]-Cycloaddition of 1,1-Diphenylsilene and 1,1-Diphenylgermene. Absolute Rate Constants for Dimerization and the Molecular Structures and Photochemistry of the Resulting 1,3-Dimetallacyclobutanes. Organometallics 1999. [DOI: 10.1021/om990447k] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Nicholas P. Toltl
- Department of Chemistry, McMaster University, 1280 Main Street West, Hamilton, Ontario, L8S 4M1 Canada
| | - Mark Stradiotto
- Department of Chemistry, McMaster University, 1280 Main Street West, Hamilton, Ontario, L8S 4M1 Canada
| | - Tracy L. Morkin
- Department of Chemistry, McMaster University, 1280 Main Street West, Hamilton, Ontario, L8S 4M1 Canada
| | - William J. Leigh
- Department of Chemistry, McMaster University, 1280 Main Street West, Hamilton, Ontario, L8S 4M1 Canada
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34
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Chajia M, Levine R. Electronically non-adiabatic transitions in high-energy CH3I+CH3I collisions computed by the quantal FMS method using the Evans–Polanyi potential. Chem Phys Lett 1999. [DOI: 10.1016/s0009-2614(99)00337-1] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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35
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Pailhous I, Ranaivonjatovo H, Escudié J, Declercq JP, Dubourg A. From a Transient 3-Germa-1-phosphabutadiene to a 1,2-Bis(phosphaalkenyl)-1,2-digermacyclobutane. Organometallics 1999. [DOI: 10.1021/om981027i] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Isabelle Pailhous
- Hétérochimie Fondamentale et Appliquée, UPRES A 5069, Université Paul Sabatier, 118 route de Narbonne, 31062 Toulouse Cedex 04, France, Laboratoire de Chimie Physique et de Cristallographie, Université Catholique de Louvain, Place Pasteur 1, B-1348 Louvain-La-Neuve, Belgium, and LAMMI, Réseau des Rayons X, Université de Montpellier II, 34095 Montpellier Cedex 5, France
| | - Henri Ranaivonjatovo
- Hétérochimie Fondamentale et Appliquée, UPRES A 5069, Université Paul Sabatier, 118 route de Narbonne, 31062 Toulouse Cedex 04, France, Laboratoire de Chimie Physique et de Cristallographie, Université Catholique de Louvain, Place Pasteur 1, B-1348 Louvain-La-Neuve, Belgium, and LAMMI, Réseau des Rayons X, Université de Montpellier II, 34095 Montpellier Cedex 5, France
| | - Jean Escudié
- Hétérochimie Fondamentale et Appliquée, UPRES A 5069, Université Paul Sabatier, 118 route de Narbonne, 31062 Toulouse Cedex 04, France, Laboratoire de Chimie Physique et de Cristallographie, Université Catholique de Louvain, Place Pasteur 1, B-1348 Louvain-La-Neuve, Belgium, and LAMMI, Réseau des Rayons X, Université de Montpellier II, 34095 Montpellier Cedex 5, France
| | - Jean-Paul Declercq
- Hétérochimie Fondamentale et Appliquée, UPRES A 5069, Université Paul Sabatier, 118 route de Narbonne, 31062 Toulouse Cedex 04, France, Laboratoire de Chimie Physique et de Cristallographie, Université Catholique de Louvain, Place Pasteur 1, B-1348 Louvain-La-Neuve, Belgium, and LAMMI, Réseau des Rayons X, Université de Montpellier II, 34095 Montpellier Cedex 5, France
| | - Antoine Dubourg
- Hétérochimie Fondamentale et Appliquée, UPRES A 5069, Université Paul Sabatier, 118 route de Narbonne, 31062 Toulouse Cedex 04, France, Laboratoire de Chimie Physique et de Cristallographie, Université Catholique de Louvain, Place Pasteur 1, B-1348 Louvain-La-Neuve, Belgium, and LAMMI, Réseau des Rayons X, Université de Montpellier II, 34095 Montpellier Cedex 5, France
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Dobrovsky I, Levine R. Electronically non-adiabatic transitions in the Evans–Polanyi valence bond model. Chem Phys Lett 1998. [DOI: 10.1016/s0009-2614(97)01459-0] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
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39
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Venturini A, Bernardi F, Olivucci M, Robb MA, Rossi I. Dimerization of Silaethylene: Computational Evidence for a Novel Mechanism for the Formation of 1,3-Disilacyclobutane via a 1,2 Approach. J Am Chem Soc 1998. [DOI: 10.1021/ja973472v] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Alessandro Venturini
- CNR-Istituto dei Composti del Carbonio contenenti Eteroatomi e loro Applicazioni, Via Gobetti 101 40129 Bologna, Italy Dipartimento di Chimica “G. Ciamician” dell' Universitá di Bologna, Via Selmi 2, 40126 Bologna, Italy Department of Chemistry, King's College London Strand, London WC2R 2LS, U.K
| | - Fernando Bernardi
- CNR-Istituto dei Composti del Carbonio contenenti Eteroatomi e loro Applicazioni, Via Gobetti 101 40129 Bologna, Italy Dipartimento di Chimica “G. Ciamician” dell' Universitá di Bologna, Via Selmi 2, 40126 Bologna, Italy Department of Chemistry, King's College London Strand, London WC2R 2LS, U.K
| | - Massimo Olivucci
- CNR-Istituto dei Composti del Carbonio contenenti Eteroatomi e loro Applicazioni, Via Gobetti 101 40129 Bologna, Italy Dipartimento di Chimica “G. Ciamician” dell' Universitá di Bologna, Via Selmi 2, 40126 Bologna, Italy Department of Chemistry, King's College London Strand, London WC2R 2LS, U.K
| | - Michael A. Robb
- CNR-Istituto dei Composti del Carbonio contenenti Eteroatomi e loro Applicazioni, Via Gobetti 101 40129 Bologna, Italy Dipartimento di Chimica “G. Ciamician” dell' Universitá di Bologna, Via Selmi 2, 40126 Bologna, Italy Department of Chemistry, King's College London Strand, London WC2R 2LS, U.K
| | - Ivan Rossi
- CNR-Istituto dei Composti del Carbonio contenenti Eteroatomi e loro Applicazioni, Via Gobetti 101 40129 Bologna, Italy Dipartimento di Chimica “G. Ciamician” dell' Universitá di Bologna, Via Selmi 2, 40126 Bologna, Italy Department of Chemistry, King's College London Strand, London WC2R 2LS, U.K
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40
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Kudin KN, Margrave JL, Khabashesku VN. Ab Initio and Density Functional Theoretical Studies of Structures, Vibrational Spectra, and Dimerization Dynamics of Simple Transient Germenes. J Phys Chem A 1998. [DOI: 10.1021/jp972006p] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
| | - John L. Margrave
- Department of Chemistry, Rice University, Houston, Texas 77005-1892
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41
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Affiliation(s)
- Mark S. Gordon
- Contribution from the Department of Chemistry, Iowa State University, Ames, Iowa 50011, and Department of Applied Chemistry, Graduate School of Engineering, University of Tokyo, 7-3-1, Hongo, Bunkyo-ku, Tokyo 113, Japan
| | - Thomas J. Barton
- Contribution from the Department of Chemistry, Iowa State University, Ames, Iowa 50011, and Department of Applied Chemistry, Graduate School of Engineering, University of Tokyo, 7-3-1, Hongo, Bunkyo-ku, Tokyo 113, Japan
| | - Haruyuki Nakano
- Contribution from the Department of Chemistry, Iowa State University, Ames, Iowa 50011, and Department of Applied Chemistry, Graduate School of Engineering, University of Tokyo, 7-3-1, Hongo, Bunkyo-ku, Tokyo 113, Japan
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42
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Voityuk AA, Rösch N. Ab Initio Study on the Structure and Splitting of the Uracil Dimer Anion Radical. J Phys Chem A 1997. [DOI: 10.1021/jp971187s] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Alexander A. Voityuk
- Institut für Physikalische and Theoretische Chemie, Technische Universität München, D-85747 Garching, Germany
| | - Notker Rösch
- Institut für Physikalische and Theoretische Chemie, Technische Universität München, D-85747 Garching, Germany
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43
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Houk KN, Nendel M, Wiest O, Storer JW. The Vinylcyclopropane−Cyclopentene Rearrangement: A Prototype Thermal Rearrangement Involving Competing Diradical Concerted and Stepwise Mechanisms. J Am Chem Soc 1997. [DOI: 10.1021/ja971315q] [Citation(s) in RCA: 77] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- K. N. Houk
- Department of Chemistry and Biochemistry University of California Los Angeles, California 90095-1569 Department of Chemistry and Biochemistry University of Notre Dame, Notre Dame, Indiana 46556
| | - Maja Nendel
- Department of Chemistry and Biochemistry University of California Los Angeles, California 90095-1569 Department of Chemistry and Biochemistry University of Notre Dame, Notre Dame, Indiana 46556
| | - Olaf Wiest
- Department of Chemistry and Biochemistry University of California Los Angeles, California 90095-1569 Department of Chemistry and Biochemistry University of Notre Dame, Notre Dame, Indiana 46556
| | - Joey W. Storer
- Department of Chemistry and Biochemistry University of California Los Angeles, California 90095-1569 Department of Chemistry and Biochemistry University of Notre Dame, Notre Dame, Indiana 46556
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44
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Martínez TJ, Ben-Nun M, Levine RD. Molecular Collision Dynamics on Several Electronic States. J Phys Chem A 1997. [DOI: 10.1021/jp970842t] [Citation(s) in RCA: 107] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Affiliation(s)
- T. J. Martínez
- Department of Chemistry, University of Illinois, Urbana, Illinois 61801
| | - M. Ben-Nun
- Department of Chemistry and Biochemistry, University of California San Diego, La Jolla, California 92093-0339
| | - R. D. Levine
- The Fritz Haber Research Center for Molecular Dynamics, The Hebrew University, Jerusalem 91904, Israel
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45
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46
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Lucero MJ, Houk KN. Conformational Transmission of Chirality: The Origin of 1,4-Asymmetric Induction in Michael Reactions of Chiral Imines. J Am Chem Soc 1997. [DOI: 10.1021/ja962819b] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Melissa J. Lucero
- Department of Chemistry and Biochemistry, University of California, Los Angeles, California 90095-1569
| | - K. N. Houk
- Department of Chemistry and Biochemistry, University of California, Los Angeles, California 90095-1569
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47
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Voityuk AA, Michel-Beyerle ME, Rösch N. A Quantum Chemical Study of Photoinduced DNA Repair: On the Splitting of Pyrimidine Model Dimers Initiated by Electron Transfer. J Am Chem Soc 1996. [DOI: 10.1021/ja961252w] [Citation(s) in RCA: 49] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Alexander A. Voityuk
- Contribution from the Institut für Physikalische and Theoretische Chemie, Technische Universität München, D-85747 Garching, Germany
| | - Maria-Elisabeth Michel-Beyerle
- Contribution from the Institut für Physikalische and Theoretische Chemie, Technische Universität München, D-85747 Garching, Germany
| | - Notker Rösch
- Contribution from the Institut für Physikalische and Theoretische Chemie, Technische Universität München, D-85747 Garching, Germany
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48
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Wilsey S, Bearpark MJ, Bernardi F, Olivucci M, Robb MA. The Role of Degenerate Biradicals in the Photorearrangement of Acylcyclopropenes to Furans. J Am Chem Soc 1996. [DOI: 10.1021/ja953726h] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Sarah Wilsey
- Contribution from the Department of Chemistry, King's College London, Strand, London WC2R 2LS, and Dipartimento di Chimica “G. Ciamician” dell'Universita di Bologna, Via Selmi 2, 40126 Bologna, Italy
| | - Michael J. Bearpark
- Contribution from the Department of Chemistry, King's College London, Strand, London WC2R 2LS, and Dipartimento di Chimica “G. Ciamician” dell'Universita di Bologna, Via Selmi 2, 40126 Bologna, Italy
| | - Fernando Bernardi
- Contribution from the Department of Chemistry, King's College London, Strand, London WC2R 2LS, and Dipartimento di Chimica “G. Ciamician” dell'Universita di Bologna, Via Selmi 2, 40126 Bologna, Italy
| | - Massimo Olivucci
- Contribution from the Department of Chemistry, King's College London, Strand, London WC2R 2LS, and Dipartimento di Chimica “G. Ciamician” dell'Universita di Bologna, Via Selmi 2, 40126 Bologna, Italy
| | - Michael A. Robb
- Contribution from the Department of Chemistry, King's College London, Strand, London WC2R 2LS, and Dipartimento di Chimica “G. Ciamician” dell'Universita di Bologna, Via Selmi 2, 40126 Bologna, Italy
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49
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Wilsey S, Bearpark MJ, Bernardi F, Olivucci M, Robb MA. Mechanism of the Oxadi-π-methane and [1,3]-Acyl Sigmatropic Rearrangements of β,γ-Enones: A Theoretical Study. J Am Chem Soc 1996. [DOI: 10.1021/ja9522802] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Sarah Wilsey
- Contribution from the Department of Chemistry, King's College London, Strand, London WC2R 2LS, U.K., and Dipartimento di Chimica “G. Ciamician” dell'Universita di Bologna, Via Selmi 2, 40126 Bologna, Italy
| | - Michael J. Bearpark
- Contribution from the Department of Chemistry, King's College London, Strand, London WC2R 2LS, U.K., and Dipartimento di Chimica “G. Ciamician” dell'Universita di Bologna, Via Selmi 2, 40126 Bologna, Italy
| | - Fernando Bernardi
- Contribution from the Department of Chemistry, King's College London, Strand, London WC2R 2LS, U.K., and Dipartimento di Chimica “G. Ciamician” dell'Universita di Bologna, Via Selmi 2, 40126 Bologna, Italy
| | - Massimo Olivucci
- Contribution from the Department of Chemistry, King's College London, Strand, London WC2R 2LS, U.K., and Dipartimento di Chimica “G. Ciamician” dell'Universita di Bologna, Via Selmi 2, 40126 Bologna, Italy
| | - Michael A. Robb
- Contribution from the Department of Chemistry, King's College London, Strand, London WC2R 2LS, U.K., and Dipartimento di Chimica “G. Ciamician” dell'Universita di Bologna, Via Selmi 2, 40126 Bologna, Italy
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