G2.光物理过程 激发态分子、自由基、离子 Electronically excited molecules are one of the three relative and unsta ble species that are encountered in the atmosphere and are strongly involved with atmospheric chemical processes The other two species are atoms or molecular fragments with unshared electrons, called free radicals, and ions consisting of electrically-charged atoms or molecular fragments. 什么叫自由基?具有孤立电子的原子或分子碎片。Electronically excited molecules are one of the three relative and unstable species that are encountered in the atmosphere and are strongly involved with atmospheric chemical processes. The other two species are atoms or molecular fragments with unshared electrons, called free radicals, and ions consisting of electrically-charged atoms or molecular fragments. 什么叫自由基？具有孤立电子的原子或分子碎片。  2. 光物理过程 激发态分子、自由基、离子