Localized and delocalized perfluorosemibullvalenes.
On the basis of the experimental Gibbs free-energy barrier of the degenerate Cope arrangement in semibullvalene, B3P86 shows the best agreement, while B3LYP and MP2 underestimate and CCSD(T) overestimates the barrier. The substituent effect proposal by Hoffmann has been verified. In contrast to semibullvalenes with either localized energy-minimum structures or delocalized transition-state structures, perfluorosemibullvalene has both localized and delocalized energy-minimum structures that are very close in energy.
Wu
Hai-Shun
HS
Department of Chemistry, Shanxi Normal University, Linfen, 041004, China. wush@dns.sxnu.edu.cn
Jia
Jianfeng
J
Jiao
Haijun
H
D020029:Base Pairing; D002244:Carbon / Q000737:chemistry*; D002625:Chemistry, Organic / Q000379:methods*; D005466:Fluorocarbons / Q000737:chemistry*; D006860:Hydrogen Bonding; D008956:Models, Chemical; D008958:Models, Molecular; D008968:Molecular Conformation; D011083:Polycyclic Compounds / Q000737:chemistry*; D012984:Software; D013329:Structure-Activity Relationship; D013816:Thermodynamics; D013941:Thymine / Q000737:chemistry
D005466:Fluorocarbons; D011083:Polycyclic Compounds; D002244:Carbon; D013941:Thymine