第一性原理研究五氯硝基苯在TiO2表面吸附
First-principles Calculation for Pentachloronitrobenzene

采用基于密度泛函理论的Materials Studio(MS)程序包中的CASTEP程序优化了锐钛矿TiO2(101)晶面、五氯硝基苯（PCNB）的结构和TiO2(101)对五氯硝基苯的16种吸附方式.计算了最佳吸附位点,吸附能,以及稳定吸附模型的电子结构.研究结果表明:五氯硝基苯中硝基的对位Cl(3),原子被垂直吸附在TiO2(101)表面的O原子时吸附能最大,吸附结构最稳定,是TiO2吸附PCNB的最佳吸附方式,吸附后C―Cl(3),键长变短,键增强,C―Cl键和C―N键增长,键变弱,吸附过程存在共价相互作用,吸附过程为化学吸附.
The crystal lattice structures of the anatase TiO2(101),the structure of Pentachoronitrob- ne(PCNB) and the 16 kinds of the modes on the TiO2(101) surface absorbed by PCNB were optimiz- ed with the CASTEP program in Materials Studio package based the density functional theory(DFT). The configurations of the best sites, the adsorption energy in the best sites and the electronic structu- res of stable adsorption models, including DOS, PDOS and electron density map, properties of the TiO2(101) before and after adsorption by PCNB have been investigated.the research result show that the absorption energy is the biggest and the absorption structure is the most stable and the adsorption mode is the best Which the mode is that when the atom Cl(3) which opposite the nitro group is in PCNB is absorbed perpendicularly by the atom O on the TiO2(101) surface .When that absorption was conducted,the C―Cl(3) bond length decreases and bond strength increases, the C―Cl and C―N bond length increases and bond strength increases. It is revealed that the covalent interaction of the PCNB on surface TiO2(101) is weak and this mode taking place chemical absorption.