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本文用量子化学从头计算法在ＨＦ／４－３１Ｇ水平上对氟氯甲烷（ＣＦＣｍｎ）分子作了计算，从分子结构参数及前沿分子轨道组合上做了详细分析。说明了随着Ｆ原子取代ＣＣ１４中Ｃ１原子的增多，分子的各化学健均增强，稳定性增加，ＨＯＭＯ能级降低，ＬＵＭＯ能级升高；ＨＯＭＯ对Ｃ－Ｆ和Ｃ－Ｃ１键都无甚键合作用，ＬＵＭＯ对Ｃ－Ｃ１起反键作用，当ＨＯＭＯ上电子被激发到ＬＵＭＯ上时，分子发生解离。造成大气平流层臭氧消耗的分子光解出来的Ｃ１原子，εＬＵＭＯ与εＨＯＭＯ差值越大，光解需要的紫外光波长越短，发生光解时在大气中的高度越高，大气滞留时间越长，解离出的Ｃ１原子消耗的臭氧分子越多。
In this paper, CFCmn molecules have been calculated from ab initio calculations at the HF / 4-31G level, and detailed analysis has been carried out on molecular structure parameters and leading molecular orbital combinations. It is shown that with the increase of C1 atom in CC14 substituted by F atom, the chemical average of each molecule increases, the stability increases, the HOMO energy level decreases, and the LUMO energy level increases. HOMO has no effect on C-F and C-C1 bonds LUMO acts as an anti-bond to C-C1, and dissociates when electrons on HOMO are excited to LUMO. The C1 atom, which causes photodecomposition of atmospheric stratospheric ozone depletion, the larger the difference between εLUMO and εHOMO, the shorter the wavelength of UV light required for photolysis, the higher the atmospheric photolysis occurs and the longer the atmospheric residence time , The dissociated C1 atoms consume more ozone molecules.