氮化铝分子及氯化锂分子结合能的量子蒙特卡罗研究

通过量子蒙特卡罗方法(QMC)利用不同的密度泛函轨道对氮化铝分子及氯化锂分子的结合能进行研究.采用扩散蒙特卡罗方法(DMC)得到氮化铝分子的结合能为2.993 eV,氯化锂分子的结合能为6.694 eV.与其他理论计算相比较,更接近实验得到氮化铝和氯化锂分子的结合能(2.862±0.391 eV和6.646 eV).同时,利用密度泛函理论对氮化铝分子及氯化锂分子的结合能进行研究时发现,利用密度泛函理论计算得到的结合能范围跨度很大且非常不准确.另外,在利用量子蒙特卡罗方法的计算中发现,不同类型的密度泛函轨道对结合能的计算产生一定的影响,这就需要在利用量子蒙特卡罗方法进行计算时考虑轨道的选择.

QuantumMonte Carlo study on the binding energies of AlN and LiCl molecules

This paper reports the studies on the binding energies of AlN and LiCl molecules by means of Quantum Monte Carlo method (QMC) with different density functional theory (DFT) orbitals (LSDA, PBE and B3LYP orbitals). For both molecules, the calculated results using Diffusion Monte Carlo (DMC) method are in excellent agreement with the experimental values. Whereas those calculated from the density functional theory method show larger differences comparing with the experimental results. In addition, we find that the DFT orbitals have a large effect on the calculated results of binding energy. So, one should carefully choose the DFT orbitals in the calculations of binding energy using Quantum Monte Carlo method.