The microwave non-thermal effect is still a controversial issue. Here, the influence of weak microwaves on the spatial collision and energy distribution of water molecules is studied by the molecular dynamics simulation. The results show that the polarization of microwaves makes the change of spatial collision and energy distribution. The spatial collision probability of water molecules increases obviously in the direction of electric field and the proportion of high energy molecules decreases while the proportion of intermediate energy molecules increases. This shows the constrains of microwave fields on the water molecules, and these consequences would be helpful to understanding the microwave non-thermal effect and the mechanism of microwaves accelerating chemical reactions.

微波的非热效应仍然是一个有争议的问题。在这里，通过分子动力学模拟研究了弱微波对水分子的空间碰撞和能量分布的影响。结果表明，微波的极化改变了空间碰撞和能量分布。水分子在电场方向上的空间碰撞概率明显增加，高能分子的比例减少，而中能分子的比例增加。这表明了微波场对水分子的约束，这些结果将有助于理解微波的非热效应以及微波加速化学反应的机理。