Departamento de Química Fisica, Universidad de Murcia, 30100 Murcia, Spain.
J Chem Phys. 2009 Nov 28;131(20):204505. doi: 10.1063/1.3266834.
The Ehrenfest method with quantum corrections is used to describe the vibrational relaxation of the bend fundamental in liquid water. All the vibrational degrees of freedom of the water molecules are described using quantum mechanics, while the remaining translational and rotational degrees of freedom are described classically. The relaxation time obtained compares well with experiment and with relaxation times calculated using other theoretical approximations. The presence of resonant intermolecular vibrational energy (VV) transfer is established with a maximum percentage of excited molecules, different from the initial one, of 9.2%. It is found through an effective kinetic fit that two VV transfers occur before relaxation of water to the vibrational ground state.
采用 Ehrenfest 方法和量子修正来描述液体水中弯曲基频的振动弛豫。使用量子力学描述水分子的所有振动自由度，而其余的平动和转动自由度则采用经典力学描述。得到的弛豫时间与实验和使用其他理论近似值计算的弛豫时间吻合得很好。通过有效的动力学拟合，确定了存在共振的分子间振动能量（VV）转移，激发分子的最大百分比与初始值不同，为 9.2%。结果发现，在水弛豫到振动基态之前，发生了两次 VV 转移。
