This paper thoroughly investigates the decomposition pathways of SF6 in the presence of organic insulator vapors by means of high level quantum chemistry calculations with density functional theory. Optimized molecular structures and vibrational frequencies of intermediate products (IM) and transition states (TS) are first reported in this work. Potential energy surface is then investigated with a more sophisticated CCSD method including zero-point energy corrections and the rate constants are calculated with transition state theory. The overall chemical decomposition pathways of SF6 + PTFE vapor are obtained which are consisted of 17 reactions with TS1–TS17. By analyzing the rate constants, reactions SF + C → S = CF → TS2 → F + SC, SF3 + C → TS7 → SF2CF → TS8 → SFCF2, SF4 + C → IM3 → TS11 → IM4 → SF3 + CF and SF5 + C → IM5 → TS15 → SF4 + CF are selected as main reactions in SF6 decomposition. The results are prerequisite to study the non-equilibrium compositions of SF6 + organic insulator vapor mixtures.

中文翻译：

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SF6 在有机绝缘蒸汽存在下的分解途径

本文通过高水平量子化学计算和密度泛函理论，深入研究了 SF6 在有机绝缘体蒸气存在下的分解途径。这项工作首次报道了中间产物 (IM) 和过渡态 (TS) 的优化分子结构和振动频率。然后使用更复杂的 CCSD 方法研究势能面，包括零点能量校正，并使用过渡态理论计算速率常数。获得了 SF6 + PTFE 蒸气的整体化学分解途径，由与 TS1-TS17 的 17 个反应组成。通过分析速率常数，反应 SF + C → S = CF → TS2 → F + SC，SF3 + C → TS7 → SF2CF → TS8 → SFCF2，SF4+C→IM3→TS11→IM4→SF3+CF和SF5+C→IM5→TS15→SF4+CF被选为SF6分解的主要反应。该结果是研究 SF6 + 有机绝缘体蒸气混合物的非平衡成分的先决条件。