【摘要】 用TEACO₂激光辐照CHCIF₂分子生成电子激发态C₂自由基,观察到斯旺带系的六个谱带。本文根据C₂分子态位能曲线的特点,提出C₂^*d³Π态的形成机制。C₂是少数较特殊的分子之一,其激发态b³Σ_g^-与第一激发态a³Π_u的位能曲线在核间距1.80A处相交。在CHCIF₂光产物的反应C+CF₂+M—→C₂^*+F₂+M中,首先形成的是C₂^*b³Σ_g^-态而不是低位的X¹Σ_g⁺态或a³Π_u态。然后通过b³Σ_g^-态与d³Π_g态的交点经无辐射跃迁到达d³Π_g态。更多还原

【Abstract】 Electronically excited radicals C₂^* were formed from CHC1F2 molecules by irradiation with a TEA CO2 laser. Six bands of Swan system have been observed. The mechanism of the formation of C₂^*d₃nΠ_g state in the infrared multiphoton dissociation of CHC1F2 is presented based on the potential energy curves of the C₂ molecule. C₂ is a somewhat unnsual molecule, the state b³∑_g^- crosses the first excited state a³Π_u at an internuclear distance of about 1.80A, and lies below it for greater nuclear separations. At first, the stateb³∑_g^- is formed in the elementary step C + CF2 + M→C₂^* + F2 + M of the reactionsof the photoproducts of CHC1F2 in preference to the low-lying X¹∑_g⁺ and a³Π_u states, and then undergoes a radiationless transition into the d³Π_g state through crossing with the d³Π_g v’ = 6 level.更多还原