纳米金刚石反应热的量子化学研究

Study on the heat of reaction of diamond nanoparticles by quantum chemistry method

为了研究纳米粒子的粒度对比表面能及其参与反应时对反应热的影响规律,本文以球形原子簇来模拟纳米金刚石颗粒,建立了计算纳米粒子比表面能和摩尔反应热的模型,用量子化学方法(AM1),对粒度不同的金刚石纳米粒子的比表面能以及与二氧化碳反应的摩尔反应热进行了计算。结果表明:纳米粒子的比表面能随其粒径的减小而增大,且随着粒径的增大比表面能减小的趋势逐渐趋于平缓,而摩尔反应热的代数值则随其粒径的增大而增大。

In order to study size dependence of the specific surface energy and the molecule heat of reaction, in this paper, nanoparticles of diamond are simulated by use of C clusters, the models of calculating specific surface energies and mole heats of reaction of diamond particles with CO, are put forward, the specific surface energies and the mole heats of reaction of diamond particles with different nano-sizes has been calculated by quantum chemistry method of AM1. The results show that when nanoparticles＇ size is increasing, the specific surface energy is decreasing and the mole heat of reaction is increasing, and the decreasing trend of the specific surface energy becomes more and more gentle.