沥青质分子聚集体中π-π相互作用的研究

Theoretical Study on π-π Interactions in Asphaltene Molecular Aggregates

采用量子力学与分子动力学相结合的方法对形成沥青质分子聚集体的分子间π-π相互作用进行了研究。结果表明:沥青质分子间的π-π相互作用能随着分子芳香环数的增加而增大;分子中含有的杂原子显著增加了沥青质分子间的π-π相互作用能;沥青质分子的支链长度及类型能够影响π-π相互作用能的大小;当沥青质分子聚集体中含有多个π-π相互作用时,其分子间的聚集作用力会大大增加;沥青质分子间形成π-π相互作用的过程中,分子间有少量的电子转移;色散作用是π-π相互作用中的主要作用。

Quantum mechanical and molecular dynamics methods were used to study the π-π interactions in asphaltene molecular aggregates.The results show that the π-π interactions between asphaltene molecules increase with the increase of molecular aromatic rings' number.The heteroatoms significantly increase the π-π interaction energies between the asphaltene molecules.The type and length of the asphaltene molecule branches show considerable influence on π-π interaction energies.When asphaltene aggregates contain multiple π-π interactions,the intermolecular interaction force increases significantly.In the process of forming π-π interactions between asphaltene molecules,a small amount of electron transfer between molecules occurs.The dispersion force is the main factor in the π-π interaction force.