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Volumn 72, Issue 15, 2007, Pages 5555-5566

Computational methods in organic thermochemistry. 1. Hydrocarbon enthalpies and free energies of formation

Author keywords

[No Author keywords available]

Indexed keywords

AROMATIC HYDROCARBONS; ATOMIZATION; COMPUTATIONAL METHODS; DENSITY FUNCTIONAL THEORY; ENTHALPY; FREE ENERGY;

EID: 34547111525     PISSN: 00223263     EISSN: None     Source Type: Journal    
DOI: 10.1021/jo070383k     Document Type: Article
Times cited : (48)

References (72)
  • 1
    • 0003363438 scopus 로고    scopus 로고
    • Neutral Thermochemical Data
    • Linstrom P. J, Mallard, W. G, Eds, National Institute of Standards and Technology: Gaithersburg, MD, June
    • Afeefy, H. Y.; Liebman, J. F.; Stein, S. E. Neutral Thermochemical Data. In NIST Chemistry WebBook, NIST Standard Reference Database, Number 69; Linstrom P. J., Mallard, W. G., Eds.; National Institute of Standards and Technology: Gaithersburg, MD, June 2005 (http://webbook.nist.gov).
    • (2005) NIST Chemistry WebBook, NIST Standard Reference Database, Number 69
    • Afeefy, H.Y.1    Liebman, J.F.2    Stein, S.E.3
  • 9
    • 23044443893 scopus 로고    scopus 로고
    • For a thorough discussion of the method, see:, University Science Books: Sausalito, CA
    • For a thorough discussion of the method, see: Anslyn, E. V.; Dougherty, D. A. Modern Physical Organic Chemistry; University Science Books: Sausalito, CA, 2005; pp 79-81.
    • (2005) Modern Physical Organic Chemistry , pp. 79-81
    • Anslyn, E.V.1    Dougherty, D.A.2
  • 33
    • 34547128681 scopus 로고    scopus 로고
    • Frisch, M. J. et. al. Gaussian 98, Revision A.11.3; Gaussian, Inc.: Pittsburgh, 1998. Complete citation is found in Supporting Information.
    • Frisch, M. J. et. al. Gaussian 98, Revision A.11.3; Gaussian, Inc.: Pittsburgh, 1998. Complete citation is found in Supporting Information.
  • 47
    • 34547102036 scopus 로고    scopus 로고
    • Reference 11, page 271
    • Reference 11, page 271.
  • 48
    • 34547109437 scopus 로고    scopus 로고
    • There are actually a number of potential bond separation equations that can be written for many of the compounds that we have examined, some of these employing more than two heavy atoms. What is critical is that the molecules selected have well-defined experimental energies
    • There are actually a number of potential bond separation equations that can be written for many of the compounds that we have examined, some of these employing more than two heavy atoms. What is critical is that the molecules selected have well-defined experimental energies.
  • 51
    • 34547118169 scopus 로고    scopus 로고
    • The NIST Compuational Chemistry Comparison and Benchmark DataBase (see ref 2) has a significant number of compounds that are included in our study. The NIST adheres to the six heavy atom limit with the exception of some aromatic compounds
    • The NIST Compuational Chemistry Comparison and Benchmark DataBase (see ref 2) has a significant number of compounds that are included in our study. The NIST adheres to the six heavy atom limit with the exception of some aromatic compounds.
  • 52
    • 34547100598 scopus 로고    scopus 로고
    • Calculations at the higher level are time-consuming. Taking a mid-sized molecule such as hexane as an example, a smaller basis set (6-311+G-(d,p)) requires under 3 h for computation. Using 3df,2p polarization functions requires in excess of 18 h, whereas a G3 calculation will be completed in just over 6 h and give much better results. Only in the size of the scratch files is the density functional more economical. The G3 scratch files are 5.6 GB, whereas those for the large density functional are only 101 MB.
    • Calculations at the higher level are time-consuming. Taking a mid-sized molecule such as hexane as an example, a smaller basis set (6-311+G-(d,p)) requires under 3 h for computation. Using 3df,2p polarization functions requires in excess of 18 h, whereas a G3 calculation will be completed in just over 6 h and give much better results. Only in the size of the scratch files is the density functional more economical. The G3 scratch files are 5.6 GB, whereas those for the large density functional are only 101 MB.
  • 57
    • 0006252494 scopus 로고    scopus 로고
    • (a) Ball, D. W. Theochem 1997, 417, 107.
    • (1997) Theochem , vol.417 , pp. 107
    • Ball, D.W.1
  • 69
    • 34547092496 scopus 로고    scopus 로고
    • Only single gauche conformers were computed. Incorporation of g+g+ conformers has an impact of less than 0.5 kJ/mol in most cases, although it is probable that consideration of such conformers would improve accuracy for large molecules such as decane.
    • Only single gauche conformers were computed. Incorporation of g+g+ conformers has an impact of less than 0.5 kJ/mol in most cases, although it is probable that consideration of such conformers would improve accuracy for large molecules such as decane.
  • 71
    • 34547107668 scopus 로고    scopus 로고
    • Enthalpies and free energies of formation calculated by all other methods may be found in Supporting Information
    • Enthalpies and free energies of formation calculated by all other methods may be found in Supporting Information.
  • 72
    • 34547101052 scopus 로고    scopus 로고
    • For example, 2,2-dimethylhexane has two rotatable bonds and 2,4-dimethyl hexane has one
    • For example, 2,2-dimethylhexane has two rotatable bonds and 2,4-dimethyl hexane has one.


* 이 정보는 Elsevier사의 SCOPUS DB에서 KISTI가 분석하여 추출한 것입니다.