We designed our research route as follows: The first step, we choose F+CH4, F+H2O as reaction systems to carry out our calculation of hydrogen abstraction, because carbon atom and oxygen atom have different affinities.

• 在选择反应体系时，首先我们选择F+CH_4、F+H_2O抽氢反应。 因为碳原子和氧原子电负性不同，而它们又属于各自独立的分子。