free-electron collision

例句：

1. 1.The free-electron collision model is used to explain the behavior of atoms and molecules in a gas.
   自由电子碰撞模型被用来解释气体中原子和分子的行为。
2. 2.In the free-electron collision, the electrons move around freely without any restrictions.
   在自由电子碰撞中，电子可以自由地移动而不受任何限制。
3. 3.The free-electron collision theory has been widely applied in various fields of science and technology.
   自由电子碰撞理论已被广泛应用于科学和技术的各个领域。