The stepwise and concerted dissociation of ground state molecule under external fields is studied for the first time with density functional theory. The geometry, the orbit energies, the dissociation properties and the IR spectrum of CF₂Br₂ under external electrical fields (-0.015 a.u.∼ 0.065 a.u.) have been calculated at the B3PW91/ 6-311+G (2df) level. The potential energy surfaces along single and two C-Br bonds under different external fields were obtained which indicate that the stepwise dissociation will happen under 0.055 a.u.. and a generally repulsive pathway which towards the concerted dissociation of ground state CF₂Br₂ exists under 0.065 a.u.(1a.u.=5.14225×10¹¹V•m^-1).

利用密度泛函理论首次研究了外场作用下基态分子的逐步协调解离。几何形状，轨道能量，解离性质和CF的IR光谱₂溴₂下的外部电场（-0.015 AU〜0.065 AU）已在B3PW91 / 6-311 + G（2DF）电平计算的。在不同的外部场下，沿单C-Br键和两个C-Br键的势能面被获得，这表明逐步解离将在0.055 au以下发生。在0.065以下存在一个通向基本态CF ₂ Br ₂协同解离的排斥路径au（1a.u. = 5.14225×10 ¹¹ V•m ^-1）。