Max-Planck-Institut für Dynamik und Selbstorganisation, D-37073 Göttingen, Germany.
J Chem Phys. 2010 Jan 28;132(4):044305. doi: 10.1063/1.3299249.
The lowest five (1)A(') states of ozone, involved in the photodissociation with UV light, are analyzed on the basis of multireference configuration interaction electronic structure calculations with emphasis on the various avoided crossings in different regions of coordinate space. Global diabatic potential energy surfaces are constructed for the lowest four states termed X, A, B, and R. In addition, the off-diagonal potentials that couple the initially excited state B with states R and A are constructed to reflect results from additional electronic structure calculations, including the calculation of nonadiabatic coupling matrix elements. The A/X and A/R couplings are also considered, although in a less ambitious manner. The photodissociation dynamics are studied by means of trajectory surface hopping (TSH) calculations with the branching ratio between the singlet, O((1)D)+O(2)((1)Delta(g)), and triplet, O((3)P)+O(2)((3)Sigma(g) (-)), channels being the main focus. The semiclassical branching ratio agrees well with quantum mechanical results except for wavelengths close to the threshold of the singlet channel. The calculated O((1)D) quantum yield is approximately 0.90-0.95 across the main part of the Hartley band, in good agreement with experimental data. TSH calculations including all four states show that transitions B-->A are relatively unimportant and subsequent transitions A-->X/R to the triplet channel are negligible.
基于多参考组态相互作用电子结构计算，分析了涉及与紫外光光解的最低五个（1）A(') 态，重点关注不同坐标空间区域的各种避免交叉。构建了最低四个态 X、A、B 和 R 的全局非绝热势能面。此外，构建了最初激发态 B 与态 R 和 A 之间的非对角势能，以反映包括非绝热耦合矩阵元计算在内的其他电子结构计算的结果。虽然方式不太激进，但也考虑了 A/X 和 A/R 耦合。通过轨迹表面跳跃（TSH）计算研究了光解动力学，其中 singlet，O((1)D)+O(2)((1)Delta(g)) 和 triplet，O((3)P)+O(2)((3)Sigma(g) (-)) 通道之间的分支比是主要关注点。除了接近单重态通道阈值的波长外，半经典分支比与量子力学结果吻合得很好。在哈特利带的主要部分，计算得到的 O((1)D) 量子产率约为 0.90-0.95，与实验数据吻合较好。包括所有四个态的 TSH 计算表明，B-->A 的跃迁相对不重要，随后 A-->X/R 到三重态通道的跃迁可以忽略不计。
