1,3,5-三硝基苯在高岭石表面吸附的理论研究

Theoretical Study on Adsorption of 1,3,5-Trinitrobenzene Molecule on Kaolinite Surface

构造了高岭石硅氧层和铝氧层的团簇模型(分别为Si13O37H22和Al6O24H30),并分别在B3LYP/6-31G(d),MP2/6-31G(d)//B3LYP/6-31G(d)和B3LYP/6-311++G(d,p)//B3LYP/6-31G(d)理论水平上对1,3,5-三硝基苯(TNB)在高岭石表面的吸附性质(如优化的几何构型、结构参数、吸附能、振动频率、静电势和分子轨道等)进行了研究.结果表明,TNB和硅氧层表面间的相互作用以静电和范德华相互作用为主;TNB与铝氧层间的相互作用以氢键为主,且TNB和铝氧层间相互作用的能量更低,结构更稳定.

The cluster models Si13O37H22and Al6O24H30for tetrahedral(Si—O) and octahedral(Al—O)surfaces of kaolinite were constructed,respectively. The properties of interaction between 1,3,5-trinitrobenzene( TNB) molecule and kaolinite surface have been studied at the levels of B3LYP /6-31G( d),MP2 /6-31G(d) / /B3LYP/6-31G(d) and B3LYP/6-311 + + G(d,p) / /B3LYP/6-31G(d),respectively.The computed properties characterizing complexes include optimal structures,structural parameters,adsorption energies,vibration frequencies,electrostatic potential maps,molecular orbitals,and so on. The results show that the interaction of TNB with the Si—O surface is governed by the electrostatic and van der Waals' interactions,and the interaction between TNB and Al—O surface is mainly provided by the hydrogen bonds. Simultaneously the binding energy between TNB molecule and Al—O surface is lower than that between TNB molecule and Si—O surface.