蒙特卡罗方法
化学
焓
密度泛函理论
分子
计算化学
热力学
液态水
标准生成焓
偶极子
标准生成焓变
物理化学
物理
有机化学
数学
统计
作者
P. Cabral do Couto,Rita C. Guedes,Benedito J. Costa Cabral,José A. Martinho Simões
摘要
The hydration of the hydroxyl OH radical has been investigated by microsolvation modeling and statistical mechanics Monte Carlo simulations. The microsolvation approach was based on density functional theory (DFT) calculations for OH–(H2O)1–6 and (H2O)1–7 clusters. The results from microsolvation indicate that the binding enthalpies of the OH radical and water molecule to small water clusters are similar. Monte Carlo simulations predict that the hydration enthalpy of the OH radical, ΔhydH(OH,g), is −39.1 kJ mol−1. From this value we have estimated that the band gap of liquid water is 6.88 eV, which is in excellent agreement with the result of Coe et al. [J. Chem. Phys. 107, 6023 (1997)]. We have compared the structure of the hydrated OH solution with the structure of pure liquid water. The structural differences between the two systems reflect the strong role played by the OH radical as a proton donor in water. From sequential Monte Carlo/DFT calculations the dipole moment of the OH radical in liquid water is 2.2±0.1 D, which is ∼33% above the experimental gas phase value (1.66 D).
科研通智能强力驱动
Strongly Powered by AbleSci AI