The C--C bond dissociation energy (BDE) is a very important data in research of hydrocarbon cracking reactions, because it reflects the difficulty level of chemical reactions. But it is very difficult to obtain the ...The C--C bond dissociation energy (BDE) is a very important data in research of hydrocarbon cracking reactions, because it reflects the difficulty level of chemical reactions. But it is very difficult to obtain the C--C bond dissociation energy (BDE) by experiments, so using quantum chemistry calculation such as density functional theory (DFT) to study the C--C bond dissociation energy is a very useful means. The impact of acceptor substituents and donor substituents on the C--C bond length distribution was studied.展开更多
The DFT-based (density fimctional theory) ab initio quantum mechanical methods have been applied to study the basicity of the nitrogen-containing compounds in petroleum. The results have indicated that there is a di...The DFT-based (density fimctional theory) ab initio quantum mechanical methods have been applied to study the basicity of the nitrogen-containing compounds in petroleum. The results have indicated that there is a distinct relationship between the protonation energy of nitrogen-containing compounds and their basicity. The more negative the protonation energy, the stronger the basicity is. It has been also found that aliphatic amines are more basic than pyridines or aromatic amines, and all these compounds are more basic than pyrroles. The addition of the aromatic rings can influence the basicity of anilines, while the 5- and 6-membered heterocyclic compounds function differently. The solvent properties may affect the basicity of these nitrogen-containing compounds.展开更多
文摘The C--C bond dissociation energy (BDE) is a very important data in research of hydrocarbon cracking reactions, because it reflects the difficulty level of chemical reactions. But it is very difficult to obtain the C--C bond dissociation energy (BDE) by experiments, so using quantum chemistry calculation such as density functional theory (DFT) to study the C--C bond dissociation energy is a very useful means. The impact of acceptor substituents and donor substituents on the C--C bond length distribution was studied.
基金supported by the"973"project envisaged in the State Key Basic R&D Program(2006CB202505).
文摘The DFT-based (density fimctional theory) ab initio quantum mechanical methods have been applied to study the basicity of the nitrogen-containing compounds in petroleum. The results have indicated that there is a distinct relationship between the protonation energy of nitrogen-containing compounds and their basicity. The more negative the protonation energy, the stronger the basicity is. It has been also found that aliphatic amines are more basic than pyridines or aromatic amines, and all these compounds are more basic than pyrroles. The addition of the aromatic rings can influence the basicity of anilines, while the 5- and 6-membered heterocyclic compounds function differently. The solvent properties may affect the basicity of these nitrogen-containing compounds.