气相氢氟烃和氢氟烯烃与·OH反应的量子化学计算方法筛选_link管理

添加链接

注册登录

link管理

链接快照平台

输入网页链接，自动生成快照
标签化管理网页链接

相关文章推荐

有腹肌的警车 · Traefik 3.x with ...· 1 月前 ·

体贴的麻辣香锅 · 《影之诗》国服人气卡牌投票结果公布！ - 哔哩哔哩· 1 月前 ·

狂野的日光灯 · 2019年宁海县国民经济和社会发展统计公报· 2 月前 ·

迷茫的海龟 · GitHub - ...· 4 月前 ·

一身肌肉的包子 · dotnet msbuild 命令 - ...· 6 月前 ·

丁保君, 姜琦, 夏德铭, 马芳芳, 陈景文. 气相氢氟烃和氢氟烯烃与·OH反应的量子化学计算方法筛选[J]. 环境化学, 2023, 42(10): 3256-3264. doi: 10.7524/j.issn.0254-6108.2022050501

引用本文: 丁保君, 姜琦, 夏德铭, 马芳芳, 陈景文. 气相氢氟烃和氢氟烯烃与·OH反应的量子化学计算方法筛选[J]. 环境化学, 2023, 42(10): 3256-3264. doi: 10.7524/j.issn.0254-6108.2022050501

DING Baojun, JIANG Qi, XIA Deming, MA Fangfang, CHEN Jingwen. Screening of quantum chemical method for the reactions of hydrofluorocarbons and hydrofluoroolefins with ·OH in the Atmosphere[J]. Environmental Chemistry, 2023, 42(10): 3256-3264. doi: 10.7524/j.issn.0254-6108.2022050501

Citation: DING Baojun, JIANG Qi, XIA Deming, MA Fangfang, CHEN Jingwen. Screening of quantum chemical method for the reactions of hydrofluorocarbons and hydrofluoroolefins with ·OH in the Atmosphere[J]. Environmental Chemistry , 2023, 42(10): 3256-3264. doi: 10.7524/j.issn.0254-6108.2022050501 Corresponding author: DING Baojun, [email protected] ;

Fund Project: the National Key Research and Development Program (2018YFC1801604, 2018YFE0110700) and the National Natural Science Foundation of China (22136001) 氢氟烃 (HFCs)和氢氟烯烃 (HFOs)常被用作氢氯氟烃的替代物. 为评估HFCs和HFOs是否可以理想替代氢氯氟烃，需要对其大气转化进行充分研究，尤其需要充分了解其大气持久性的信息. 目前用于评估化学品大气持久性的重要参数气相羟基自由基(·OH)二级反应速率常数( k _OH )的数据量尚不能满足多种HFCs和HFOs的评估. 因此有必要发展能够快速预测 k _OH 的方法. 量子化学计算方法具有高效、准确的优点，是预测 k _OH 的重要手段. 然而目前研究使用的量子化学方法纷繁复杂，亟需筛选适合HFCs和HFOs的量子化学方法. 本研究基于3种HFCs(CF ₃ CF ₂ H、CF ₃ CH ₂ CF ₃ 和CF ₃ CF ₂ (CHF) ₂ CF ₃ )和2个HFOs(CF ₂ CH ₂ 和CF ₃ CH ₂ CF ₃ )的实验数据，从多种热力学参数计算方法和动力学计算方法中筛选适用于计算HFCs和HFOs气相 k _OH 的方法. 研究结果表明，通过对比lg k _OH 的实测值与不同计算方法所得计算值之间的平均绝对误差(MAE)，利用Skodje-Truhlar隧道效应校正系数 ( κ _S )修正传统过渡态理论(TST)，再结合M06-2X-D3/def2-TZVP//M06-2X/cc-pVDZ水平的密度泛函理论(DFT)计算HFCs的 k _OH 效果最好，其MAE值为0.17；采用Wigner隧道效应校正系数 ( κ _W )修正的TST结合M06-2X-D3/aug-cc-pVTZ//M06-2X/cc-pVDZ (MAE = 0.50)的方法计算HFOs的 k _OH 效果最好；而 κ _S 修正TST的M06-2X-D3/aug-cc-pVTZ//M06-2X/cc-pVDZ (MAE = 0.34)或M06-2X-D3/jul-cc-pVTZ//M06-2X/cc-pVDZ (MAE = 0.35)方法都适用于计算HFCs和HFOs的 k _OH . 本研究筛选的方法为快速、准确计算HFCs和HFOs的 k _OH 及评估其大气持久性提供了方法支撑. 氢氟烃 (HFCs) 氢氟烯烃 (HFOs) 量子化学计算密度泛函理论(DFT) Abstract: Hydrofluorocarbons (HFCs) and hydrofluoroolefins (HFOs) are mainly employed to substitute hydrochlorofluorocarbons. In order to evaluate whether the HFCs and HFOs are ideal alternatives for hydrochlorofluorocarbons or not, it is necessary to fully explore their atmospheric transformation, especially the information atmospheric persistence. To date, the quantity of second-order reaction rate constants ( k _OH ) for chemicals reacting with hydroxyl radicals (·OH), which are essential parameters to characterize the atmospheric persistence of HFCs and HFOs, cannot meet the needs of atmospheric persistence assessment for HFCs and HFOs. Therefore, it is necessary to develop a method that can predict the k _OH values efficiently. Considering the efficiency and accuracy of quantum chemical calculation, quantum chemical calculation is an important way to predict the k _OH values. However, the quantum chemistry methods used in the current research are complex, and it is urgent to screen the quantum chemistry methods that are suitable for HFCs and HFOs. In this study, suitable methods for predicting the atmospheric k _OH values of HFCs and HFOs were selected from a variety of thermodynamic parameter calculation methods and kinetics calculation methods based on the experimental data of 3 HFCs (CF ₃ CF ₂ H, CF ₃ CH ₂ CF ₃ , and CF ₃ CF ₂ (CHF) ₂ CF ₃ ) and 2 HFOs (CF ₂ CH ₂ and CF ₃ CH ₂ CF ₃ ). The research results show that by comparing the mean absolute error (MAE) between the experimental lg k _OH values and the lg k _OH values calculated by different theoretical methods, the method employing the traditional transition state theory (TST) modified with the Skodje-Truhlar tunnel effect correction coefficient( κ _S ) and combining with the density functional theory (DFT) at the M06-2X-D3/def2-TZVP//M06-2X/cc-pVDZ level has the best effect on calculating the k _OH of HFCs accurately, whose MAE was 0.17; The method employing TST method modified with Wigner transmission coefficient ( κ _W ) and combining with the M06-2X-D3/aug-cc-pVTZ//M06-2X/cc-pVDZ (MAE= 0.50) showed the best performance for calculating the k _OH values of HFOs; Both of the two methods that TST modified with the κ _W correction combine with M06-2X-D3/aug-cc-pVTZ//M06-2X/cc-pVDZ (MAE = 0.34) or M06-2X-D3/jul-cc-pVTZ//M06-2X/cc-pVDZ (MAE = 0.35) were suitable for the k _OH prediction of HFCs and HFOs. In this study, the selected methods provide efficient and accurate methods for the k _OH calculation and atmospheric persistence assessment of HFCs and HFOs. Key words: hydrofluorocarbons (HFCs) hydrofluoroolefins (HFOs) OH radicals quantum chemical calculation density functional theory (DFT) kinetics. 单点能方法
Zero-point energy method κ 化合物
CompoundCF ₃ CF ₂ HCF ₃ CH ₂ CF ₃ CF ₃ CF ₂ (CHF) ₂ CF ₃ CF ₂ =CH ₂ CF ₃ (CF ₂ ) ₇ CH=CH ₂ 实测值6.25 × 10 ⁻¹⁵ 9.57 × 10 ⁻¹⁶ 3.29 × 10 ⁻¹⁵ 2.49 × 10 ⁻¹² 1.36 × 10 ⁻¹² M06-2X-D3/aug-cc-pVTZ κ _S 4.11 × 10 ⁻¹⁵ 1.16 × 10 ⁻¹⁵ 8.55 × 10 ⁻¹⁵ 1.58 × 10 ⁻¹² 1.34 × 10 ⁻¹³ κ _W 1.27 × 10 ⁻¹⁵ 1.79 × 10 ⁻¹⁶ 3.98 × 10 ⁻¹⁵ 1.55 × 10 ⁻¹² 1.84 × 10 ⁻¹³ M06-2X-D3/may-cc-pVTZ κ _S 3.19 × 10 ⁻¹⁵ 9.33 × 10 ⁻¹⁶ 6.86 × 10 ⁻¹⁵ 8.18 × 10 ⁻¹³ 1.22 × 10 ⁻¹³ κ _W 9.22 × 10 ⁻¹⁶ 1.35 × 10 ⁻¹⁶ 2.96 × 10 ⁻¹⁵ 1.02 × 10 ⁻¹² 1.48 × 10 ⁻¹³ M06-2X-D3/jun-cc-pVTZ κ _S 3.50 × 10 ⁻¹⁵ 1.01 × 10 ⁻¹⁵ 7.28 × 10 ⁻¹⁵ 1.23× 10 ⁻¹² 1.24 × 10 ⁻¹³ κ _W 1.03 × 10 ⁻¹⁵ 1.49 × 10 ⁻¹⁶ 3.20 × 10 ⁻¹⁵ 1.20 × 10 ⁻¹² 1.55 × 10 ⁻¹³ M06-2X-D3/jul-cc-pVTZ κ _S 3.78 × 10 ⁻¹⁵ 1.10 × 10 ⁻¹⁵ 8.05 × 10 ⁻¹⁵ 1.51 × 10 ⁻¹² 1.31 × 10 ⁻¹³ κ _W 1.14 × 10 ⁻¹⁵ 1.67 × 10 ⁻¹⁶ 3.67 × 10 ⁻¹⁵ 1.48 × 10 ⁻¹² 1.73 × 10 ⁻¹³ M06-2X-D3/def2-TZVP κ _S 2.96 × 10 ⁻¹⁵ 9.03 × 10 ⁻¹⁶ 6.51 × 10 ⁻¹⁵ 8.07× 10 ⁻¹³ 1.33 × 10 ⁻¹³ κ _W 8.40 × 10 ⁻¹⁶ 1.29 × 10 ⁻¹⁶ 2.75 × 10 ⁻¹⁵ 9.62 × 10 ⁻¹³ 1.88 × 10 ⁻¹³ M06-2X-D3/def2-TZVPP κ _S 4.27 × 10 ⁻¹⁵ 1.12 × 10 ⁻¹⁵ 8.28 × 10 ⁻¹⁵ 7.25 × 10 ⁻¹³ 1.14 × 10 ⁻¹³ κ _W 1.33 × 10 ⁻¹⁵ 1.71 × 10 ⁻¹⁶ 3.80 × 10 ⁻¹⁵ 8.58 × 10 ⁻¹³ 1.34 × 10 ⁻¹³ M06-2X-D3/pcseg-2 κ _S 2.50 × 10 ⁻¹⁵ 6.47 × 10 ⁻¹⁶ 5.31 × 10 ⁻¹⁵ 4.81 × 10 ⁻¹³ 7.27 × 10 ⁻¹⁴ κ _W 6.79 × 10 ⁻¹⁶ 8.47 × 10 ⁻¹⁷ 2.10 × 10 ⁻¹⁵ 5.57 × 10 ⁻¹³ 7.52 × 10 ⁻¹⁴ M06-2X-D3/MG3S κ _S 4.16 × 10 ⁻¹⁵ 1.18 × 10 ⁻¹⁵ 1.18 × 10 ⁻¹⁴ 1.59 × 10 ⁻¹² 1.32 × 10 ⁻¹³ κ _W 1.29 × 10 ⁻¹⁵ 1.82 × 10 ⁻¹⁶ 6.08 × 10 ⁻¹⁵ 1.56 × 10 ⁻¹² 1.71 × 10 ⁻¹³ ωB97X-D/aug-cc-pVTZ κ _S 3.99 × 10 ⁻¹⁴ 4.43 × 10 ⁻¹⁵ 3.45 × 10 ⁻¹⁴ 5.10 × 10 ⁻¹¹ 4.72 × 10 ⁻¹² κ _W 2.72 × 10 ⁻¹⁴ 1.08 × 10 ⁻¹⁵ 2.96 × 10 ⁻¹⁴ 4.99 × 10 ⁻¹¹ 4.54 × 10 ⁻¹² ωB97X-D/may-cc-pVTZ κ _S 3.34 × 10 ⁻¹⁴ 3.65 × 10 ⁻¹⁵ 2.92 × 10 ⁻¹⁴ 3.51 × 10 ⁻¹¹ 3.84 × 10 ⁻¹² κ _W 2.08 × 10 ⁻¹⁴ 8.32 × 10 ⁻¹⁶ 2.26 × 10 ⁻¹⁴ 3.44 × 10 ⁻¹¹ 3.69 × 10 ⁻¹² ωB97X-D/jun-cc-pVTZ κ _S 3.57 × 10 ⁻¹⁴ 3.97 × 10 ⁻¹⁵ 3.09 × 10 ⁻¹⁴ 4.17 × 10 ⁻¹¹ 4.10 × 10 ⁻¹² κ _W 2.30 × 10 ⁻¹⁴ 9.34 × 10 ⁻¹⁶ 2.48 × 10 ⁻¹⁴ 4.11 × 10 ⁻¹¹ 3.94 × 10 ⁻¹² ωB97X-D/jul-cc-pVTZ κ _S 3.75 × 10 ⁻¹⁴ 4.24 × 10 ⁻¹⁵ 3.31 × 10 ⁻¹⁴ 4.88 × 10 ⁻¹¹ 4.51 × 10 ⁻¹² κ _W 2.47 × 10 ⁻¹⁴ 1.02 × 10 ⁻¹⁵ 2.77× 10 ⁻¹⁴ 4.78 × 10 ⁻¹¹ 4.34 × 10 ⁻¹² ωB97X-D/def2-TZVP κ _S 3.43 × 10 ⁻¹⁴ 4.49 × 10 ⁻¹⁵ 3.27 × 10 ⁻¹⁴ 2.94 × 10 ⁻¹¹ 5.78 × 10 ⁻¹² κ _W 2.17 × 10 ⁻¹⁴ 1.09 × 10 ⁻¹⁵ 2.71 × 10 ⁻¹⁴ 2.88 × 10 ⁻¹¹ 5.56 × 10 ⁻¹² ωB97X-D/def2-TZVPP κ _S 4.29 × 10 ⁻¹⁴ 5.29 × 10 ⁻¹⁵ 3.70 × 10 ⁻¹⁴ 2.99 × 10 ⁻¹¹ 4.56 × 10 ⁻¹² κ _W 3.07 × 10 ⁻¹⁴ 1.36 × 10 ⁻¹⁵ 3.33 × 10 ⁻¹⁴ 2.93 × 10 ⁻¹¹ 4.38 × 10 ⁻¹² ωB97X-D/pcseg-2 κ _S 2.53 × 10 ⁻¹⁴ 2.93 × 10 ⁻¹⁵ 2.35 × 10 ⁻¹⁴ 2.06 × 10 ⁻¹¹ 2.58 × 10 ⁻¹² κ _W 1.40 × 10 ⁻¹⁴ 6.24 × 10 ⁻¹⁶ 1.63 × 10 ⁻¹⁴ 2.01 × 10 ⁻¹¹ 2.53 × 10 ⁻¹² ωB97X-D/MG3S κ _S 4.93× 10 ⁻¹⁴ 5.99 × 10 ⁻¹⁵ 5.07 × 10 ⁻¹⁴ 8.90 × 10 ⁻¹¹ 1.08 × 10 ⁻¹¹ κ _W 3.75 × 10 ⁻¹⁴ 1.59 × 10 ⁻¹⁵ 5.65 × 10 ⁻¹⁴ 8.71 × 10 ⁻¹¹ 1.04 × 10 ⁻¹¹ 单点能方法
Zero-point energy method κ 化合物
CompoundCF ₃ CF ₂ HCF ₃ CH ₂ CF ₃ CF ₃ CF ₂ (CHF) ₂ CF ₃ CF ₂ =CH ₂ CF ₃ (CF ₂ ) ₇ CH=CH ₂ 实测值6.25 × 10 ⁻¹⁵ 9.57 × 10 ⁻¹⁶ 3.29 × 10 ⁻¹⁵ 2.49 × 10 ⁻¹² 1.36 × 10 ⁻¹² M06-2X-D3/aug-cc-pVTZ κ _S 4.11 × 10 ⁻¹⁵ 1.16 × 10 ⁻¹⁵ 8.55 × 10 ⁻¹⁵ 1.58 × 10 ⁻¹² 1.34 × 10 ⁻¹³ κ _W 1.27 × 10 ⁻¹⁵ 1.79 × 10 ⁻¹⁶ 3.98 × 10 ⁻¹⁵ 1.55 × 10 ⁻¹² 1.84 × 10 ⁻¹³ M06-2X-D3/may-cc-pVTZ κ _S 3.19 × 10 ⁻¹⁵ 9.33 × 10 ⁻¹⁶ 6.86 × 10 ⁻¹⁵ 8.18 × 10 ⁻¹³ 1.22 × 10 ⁻¹³ κ _W 9.22 × 10 ⁻¹⁶ 1.35 × 10 ⁻¹⁶ 2.96 × 10 ⁻¹⁵ 1.02 × 10 ⁻¹² 1.48 × 10 ⁻¹³ M06-2X-D3/jun-cc-pVTZ κ _S 3.50 × 10 ⁻¹⁵ 1.01 × 10 ⁻¹⁵ 7.28 × 10 ⁻¹⁵ 1.23× 10 ⁻¹² 1.24 × 10 ⁻¹³ κ _W 1.03 × 10 ⁻¹⁵ 1.49 × 10 ⁻¹⁶ 3.20 × 10 ⁻¹⁵ 1.20 × 10 ⁻¹² 1.55 × 10 ⁻¹³ M06-2X-D3/jul-cc-pVTZ κ _S 3.78 × 10 ⁻¹⁵ 1.10 × 10 ⁻¹⁵ 8.05 × 10 ⁻¹⁵ 1.51 × 10 ⁻¹² 1.31 × 10 ⁻¹³ κ _W 1.14 × 10 ⁻¹⁵ 1.67 × 10 ⁻¹⁶ 3.67 × 10 ⁻¹⁵ 1.48 × 10 ⁻¹² 1.73 × 10 ⁻¹³ M06-2X-D3/def2-TZVP κ _S 2.96 × 10 ⁻¹⁵ 9.03 × 10 ⁻¹⁶ 6.51 × 10 ⁻¹⁵ 8.07× 10 ⁻¹³ 1.33 × 10 ⁻¹³ κ _W 8.40 × 10 ⁻¹⁶ 1.29 × 10 ⁻¹⁶ 2.75 × 10 ⁻¹⁵ 9.62 × 10 ⁻¹³ 1.88 × 10 ⁻¹³ M06-2X-D3/def2-TZVPP κ _S 4.27 × 10 ⁻¹⁵ 1.12 × 10 ⁻¹⁵ 8.28 × 10 ⁻¹⁵ 7.25 × 10 ⁻¹³ 1.14 × 10 ⁻¹³ κ _W 1.33 × 10 ⁻¹⁵ 1.71 × 10 ⁻¹⁶ 3.80 × 10 ⁻¹⁵ 8.58 × 10 ⁻¹³ 1.34 × 10 ⁻¹³ M06-2X-D3/pcseg-2 κ _S 2.50 × 10 ⁻¹⁵ 6.47 × 10 ⁻¹⁶ 5.31 × 10 ⁻¹⁵ 4.81 × 10 ⁻¹³ 7.27 × 10 ⁻¹⁴ κ _W 6.79 × 10 ⁻¹⁶ 8.47 × 10 ⁻¹⁷ 2.10 × 10 ⁻¹⁵ 5.57 × 10 ⁻¹³ 7.52 × 10 ⁻¹⁴ M06-2X-D3/MG3S κ _S 4.16 × 10 ⁻¹⁵ 1.18 × 10 ⁻¹⁵ 1.18 × 10 ⁻¹⁴ 1.59 × 10 ⁻¹² 1.32 × 10 ⁻¹³ κ _W 1.29 × 10 ⁻¹⁵ 1.82 × 10 ⁻¹⁶ 6.08 × 10 ⁻¹⁵ 1.56 × 10 ⁻¹² 1.71 × 10 ⁻¹³ ωB97X-D/aug-cc-pVTZ κ _S 3.99 × 10 ⁻¹⁴ 4.43 × 10 ⁻¹⁵ 3.45 × 10 ⁻¹⁴ 5.10 × 10 ⁻¹¹ 4.72 × 10 ⁻¹² κ _W 2.72 × 10 ⁻¹⁴ 1.08 × 10 ⁻¹⁵ 2.96 × 10 ⁻¹⁴ 4.99 × 10 ⁻¹¹ 4.54 × 10 ⁻¹² ωB97X-D/may-cc-pVTZ κ _S 3.34 × 10 ⁻¹⁴ 3.65 × 10 ⁻¹⁵ 2.92 × 10 ⁻¹⁴ 3.51 × 10 ⁻¹¹ 3.84 × 10 ⁻¹² κ _W 2.08 × 10 ⁻¹⁴ 8.32 × 10 ⁻¹⁶ 2.26 × 10 ⁻¹⁴ 3.44 × 10 ⁻¹¹ 3.69 × 10 ⁻¹² ωB97X-D/jun-cc-pVTZ κ _S 3.57 × 10 ⁻¹⁴ 3.97 × 10 ⁻¹⁵ 3.09 × 10 ⁻¹⁴ 4.17 × 10 ⁻¹¹ 4.10 × 10 ⁻¹² κ _W 2.30 × 10 ⁻¹⁴ 9.34 × 10 ⁻¹⁶ 2.48 × 10 ⁻¹⁴ 4.11 × 10 ⁻¹¹ 3.94 × 10 ⁻¹² ωB97X-D/jul-cc-pVTZ κ _S 3.75 × 10 ⁻¹⁴ 4.24 × 10 ⁻¹⁵ 3.31 × 10 ⁻¹⁴ 4.88 × 10 ⁻¹¹ 4.51 × 10 ⁻¹² κ _W 2.47 × 10 ⁻¹⁴ 1.02 × 10 ⁻¹⁵ 2.77× 10 ⁻¹⁴ 4.78 × 10 ⁻¹¹ 4.34 × 10 ⁻¹² ωB97X-D/def2-TZVP κ _S 3.43 × 10 ⁻¹⁴ 4.49 × 10 ⁻¹⁵ 3.27 × 10 ⁻¹⁴ 2.94 × 10 ⁻¹¹ 5.78 × 10 ⁻¹² κ _W 2.17 × 10 ⁻¹⁴ 1.09 × 10 ⁻¹⁵ 2.71 × 10 ⁻¹⁴ 2.88 × 10 ⁻¹¹ 5.56 × 10 ⁻¹² ωB97X-D/def2-TZVPP κ _S 4.29 × 10 ⁻¹⁴ 5.29 × 10 ⁻¹⁵ 3.70 × 10 ⁻¹⁴ 2.99 × 10 ⁻¹¹ 4.56 × 10 ⁻¹² κ _W 3.07 × 10 ⁻¹⁴ 1.36 × 10 ⁻¹⁵ 3.33 × 10 ⁻¹⁴ 2.93 × 10 ⁻¹¹ 4.38 × 10 ⁻¹² ωB97X-D/pcseg-2 κ _S 2.53 × 10 ⁻¹⁴ 2.93 × 10 ⁻¹⁵ 2.35 × 10 ⁻¹⁴ 2.06 × 10 ⁻¹¹ 2.58 × 10 ⁻¹² κ _W 1.40 × 10 ⁻¹⁴ 6.24 × 10 ⁻¹⁶ 1.63 × 10 ⁻¹⁴ 2.01 × 10 ⁻¹¹ 2.53 × 10 ⁻¹² ωB97X-D/MG3S κ _S 4.93× 10 ⁻¹⁴ 5.99 × 10 ⁻¹⁵ 5.07 × 10 ⁻¹⁴ 8.90 × 10 ⁻¹¹ 1.08 × 10 ⁻¹¹ κ _W 3.75 × 10 ⁻¹⁴ 1.59 × 10 ⁻¹⁵ 5.65 × 10 ⁻¹⁴ 8.71 × 10 ⁻¹¹ 1.04 × 10 ⁻¹¹ 单点能方法

Zero-point energy methodMAE （TST × κ _W ）MAE （TST × κ _S ）HFCs和HFCsHFCsHFOsHFCs和HFCsHFCsHFOs M06-2X-D3/aug-cc-pVTZ0.470.450.500.340.200.56M06-2X-D3/may-cc-pVTZ0.570.530.640.390.170.72M06-2X-D3/jun-cc-pVTZ0.530.490.590.360.180.63M06-2X-D3/jul-cc-pVTZ0.490.460.520.350.190.58M06-2X-D3/def2-TZVP0.580.560.600.380.170.69M06-2X-D3/def2-TZVPP0.540.440.690.410.180.75M06-2X-D3/pcseg-20.780.690.910.500.210.93M06-2X-D3/MG3S0.510.510.510.370.240.56ωB97x-D/aug-cc-pVTZ0.740.590.950.910.870.97ωB97X-D/may-cc-pVTZ0.630.500.830.810.800.84ωB97X-D/jun-cc-pVTZ0.660.520.880.850.830.89ωB97X-D/jul-cc-pVTZ0.710.560.930.890.850.95ωB97X-D/def2-TZVP0.680.550.880.860.850.89ωB97X-D/def2-TZVPP0.730.660.830.890.920.84ωB97X-D/pcseg-20.510.430.630.670.690.64ωB97X-D/MG3S0.970.791.251.111.001.27 单点能方法

Zero-point energy methodMAE （TST × κ _W ）MAE （TST × κ _S ）HFCs和HFCsHFCsHFOsHFCs和HFCsHFCsHFOs M06-2X-D3/aug-cc-pVTZ0.470.450.500.340.200.56M06-2X-D3/may-cc-pVTZ0.570.530.640.390.170.72M06-2X-D3/jun-cc-pVTZ0.530.490.590.360.180.63M06-2X-D3/jul-cc-pVTZ0.490.460.520.350.190.58M06-2X-D3/def2-TZVP0.580.560.600.380.170.69M06-2X-D3/def2-TZVPP0.540.440.690.410.180.75M06-2X-D3/pcseg-20.780.690.910.500.210.93M06-2X-D3/MG3S0.510.510.510.370.240.56ωB97x-D/aug-cc-pVTZ0.740.590.950.910.870.97ωB97X-D/may-cc-pVTZ0.630.500.830.810.800.84ωB97X-D/jun-cc-pVTZ0.660.520.880.850.830.89ωB97X-D/jul-cc-pVTZ0.710.560.930.890.850.95ωB97X-D/def2-TZVP0.680.550.880.860.850.89ωB97X-D/def2-TZVPP0.730.660.830.890.920.84ωB97X-D/pcseg-20.510.430.630.670.690.64ωB97X-D/MG3S0.970.791.251.111.001.27 反应通道
Reaction pathway κ 单点能方法
Zero-point energy methodΔ G ^‡,0 ∆ E Δ H υ _i ^† k _OH CF ₃ CH ₂ F实测 k _OH ：6.25 × 10 ⁻¹⁵ 计算 k _OH ：2.96 × 10 ⁻¹⁵ 1a, 2a κ _S M06-2X-D3/def2-TZVP52.9017.71−62.671461.491.48 × 10 ⁻¹⁵ CF ₃ CH ₂ CF ₃ 实测 k _OH ：9.57 × 10 ⁻¹⁶ 计算 k _OH ：9.03× 10 ⁻¹⁶ 1b κ _S M06-2X-D3/def2-TZVP58.0723.16−46.481575.734.00 × 10 ⁻¹⁶ 2b κ _S M06-2X-D3/def2-TZVP57.6122.83−43.771600.205.03 × 10 ⁻¹⁶ CF ₃ CF ₂ (CHF) ₂ CF ₃ 实测 k _OH ：3.29 × 10 ⁻¹⁵ 计算 k _OH ：6.51 × 10 ⁻¹⁵ 1c κ _S M06-2X-D3/def2-TZVP52.0815.42−73.121486.681.79 × 10 ⁻¹⁵ 2cM06-2X-D3/def2-TZVP48.7712.75−74.711429.224.73 × 10 ⁻¹⁵ CF ₂ =CH ₂ 实测 k _OH ：2.49 × 10 ⁻¹² 计算 k _OH ：1.55 × 10 ⁻¹² 1d, 2d κ _W M06-2X-D3/aug-cc-pVTZ67.088.22−3.111344.441.23 × 10 ⁻¹⁸ 3d, 4d κ _W M06-2X-D3/aug-cc-pVTZ33.54−0.15−128.79437.724.00 × 10 ⁻¹³ 5d, 6d κ _W M06-2X-D3/aug-cc-pVTZ33.62−0.64−186.12392.383.76 × 10 ⁻¹³ CF ₃ (CF ₂ ) ₇ CH=CH ₂ 实测 k _OH ：1.36 × 10 ⁻¹² 计算 k _OH ：1.84 × 10 ⁻¹³ 1e κ _W M06-2X-D3/aug-cc-pVTZ59.0625.11−25.631532.353.73 × 10 ⁻¹⁷ 2e κ _W M06-2X-D3/aug-cc-pVTZ61.9725.33−24.341619.521.25 × 10 ⁻¹⁷ 3e κ _W M06-2X-D3/aug-cc-pVTZ60.4025.27−23.021527.162.16 × 10 ⁻¹⁷ 4e κ _W M06-2X-D3/aug-cc-pVTZ43.506.34−129.20536.447.76 × 10 ⁻¹⁵ 5e κ _W M06-2X-D3/aug-cc-pVTZ35.720.64−127.38497.651.74 × 10 ⁻¹³ 6e κ _W M06-2X-D3/aug-cc-pVTZ46.688.99−118.41470.142.04 × 10 ⁻¹⁵ 反应通道
Reaction pathway κ 单点能方法
Zero-point energy methodΔ G ^‡,0 ∆ E Δ H υ _i ^† k _OH CF ₃ CH ₂ F实测 k _OH ：6.25 × 10 ⁻¹⁵ 计算 k _OH ：2.96 × 10 ⁻¹⁵ 1a, 2a κ _S M06-2X-D3/def2-TZVP52.9017.71−62.671461.491.48 × 10 ⁻¹⁵ CF ₃ CH ₂ CF ₃ 实测 k _OH ：9.57 × 10 ⁻¹⁶ 计算 k _OH ：9.03× 10 ⁻¹⁶ 1b κ _S M06-2X-D3/def2-TZVP58.0723.16−46.481575.734.00 × 10 ⁻¹⁶ 2b κ _S M06-2X-D3/def2-TZVP57.6122.83−43.771600.205.03 × 10 ⁻¹⁶ CF ₃ CF ₂ (CHF) ₂ CF ₃ 实测 k _OH ：3.29 × 10 ⁻¹⁵ 计算 k _OH ：6.51 × 10 ⁻¹⁵ 1c κ _S M06-2X-D3/def2-TZVP52.0815.42−73.121486.681.79 × 10 ⁻¹⁵ 2cM06-2X-D3/def2-TZVP48.7712.75−74.711429.224.73 × 10 ⁻¹⁵ CF ₂ =CH ₂ 实测 k _OH ：2.49 × 10 ⁻¹² 计算 k _OH ：1.55 × 10 ⁻¹² 1d, 2d κ _W M06-2X-D3/aug-cc-pVTZ67.088.22−3.111344.441.23 × 10 ⁻¹⁸ 3d, 4d κ _W M06-2X-D3/aug-cc-pVTZ33.54−0.15−128.79437.724.00 × 10 ⁻¹³ 5d, 6d κ _W M06-2X-D3/aug-cc-pVTZ33.62−0.64−186.12392.383.76 × 10 ⁻¹³ CF ₃ (CF ₂ ) ₇ CH=CH ₂ 实测 k _OH ：1.36 × 10 ⁻¹² 计算 k _OH ：1.84 × 10 ⁻¹³ 1e κ _W M06-2X-D3/aug-cc-pVTZ59.0625.11−25.631532.353.73 × 10 ⁻¹⁷ 2e κ _W M06-2X-D3/aug-cc-pVTZ61.9725.33−24.341619.521.25 × 10 ⁻¹⁷ 3e κ _W M06-2X-D3/aug-cc-pVTZ60.4025.27−23.021527.162.16 × 10 ⁻¹⁷ 4e κ _W M06-2X-D3/aug-cc-pVTZ43.506.34−129.20536.447.76 × 10 ⁻¹⁵ 5e κ _W M06-2X-D3/aug-cc-pVTZ35.720.64−127.38497.651.74 × 10 ⁻¹³ 6e κ _W M06-2X-D3/aug-cc-pVTZ46.688.99−118.41470.142.04 × 10 ⁻¹⁵ ZHAO Y, TRUHLAR D G. The M06 suite of density functionals for main group thermochemistry, thermochemical kinetics, noncovalent interactions, excited states, and transition elements: Two new functionals and systematic testing of four M06-class functionals and 12 other functionals [J]. Theoretical Chemistry Accounts, 2008, 120(1): 215-241. DOUBLEDAY C, ARMAS R, WALKER D, et al. Heavy-atom tunneling calculations in thirteen organic reactions: Tunneling contributions are substantial, and Bell's formula closely approximates multidimensional tunneling at ≥250 K [J]. Angewandte Chemie (International Ed. in English), 2017, 56(42): 13099-13102. doi: 10.1002/anie.201708489

摘要: 氢氟烃 (HFCs)和氢氟烯烃 (HFOs)常被用作氢氯氟烃的替代物. 为评估HFCs和HFOs是否可以理想替代氢氯氟烃，需要对其大气转化进行充分研究，尤其需要充分了解其大气持久性的信息. 目前用于评估化学品大气持久性的重要参数气相羟基自由基(·OH)二级反应速率常数( k _OH )的数据量尚不能满足多种HFCs和HFOs的评估. 因此有必要发展能够快速预测 k _OH 的方法. 量子化学计算方法具有高效、准确的优点，是预测 k _OH 的重要手段. 然而目前研究使用的量子化学方法纷繁复杂，亟需筛选适合HFCs和HFOs的量子化学方法. 本研究基于3种HFCs(CF ₃ CF ₂ H、CF ₃ CH ₂ CF ₃ 和CF ₃ CF ₂ (CHF) ₂ CF ₃ )和2个HFOs(CF ₂ CH ₂ 和CF ₃ CH ₂ CF ₃ )的实验数据，从多种热力学参数计算方法和动力学计算方法中筛选适用于计算HFCs和HFOs气相 k _OH 的方法. 研究结果表明，通过对比lg k _OH 的实测值与不同计算方法所得计算值之间的平均绝对误差(MAE)，利用Skodje-Truhlar隧道效应校正系数 ( κ _S )修正传统过渡态理论(TST)，再结合M06-2X-D3/def2-TZVP//M06-2X/cc-pVDZ水平的密度泛函理论(DFT)计算HFCs的 k _OH 效果最好，其MAE值为0.17；采用Wigner隧道效应校正系数 ( κ _W )修正的TST结合M06-2X-D3/aug-cc-pVTZ//M06-2X/cc-pVDZ (MAE = 0.50)的方法计算HFOs的 k _OH 效果最好；而 κ _S 修正TST的M06-2X-D3/aug-cc-pVTZ//M06-2X/cc-pVDZ (MAE = 0.34)或M06-2X-D3/jul-cc-pVTZ//M06-2X/cc-pVDZ (MAE = 0.35)方法都适用于计算HFCs和HFOs的 k _OH . 本研究筛选的方法为快速、准确计算HFCs和HFOs的 k _OH 及评估其大气持久性提供了方法支撑.

Corresponding author: DING Baojun, [email protected] ;

1. School of Chemical Engineering, Dalian University of Technology, Dalian , 116024, China

2. Key Laboratory of Industrial Ecology and Environmental Engineering (Ministry of Education), Department of Environmental Science and Technology, Dalian University of Technology, Dalian, 116024, China

Received Date: 2022-05-05

Accepted Date: 2022-06-24

Available Online: 2023-10-23

Fund Project: the National Key Research and Development Program (2018YFC1801604, 2018YFE0110700) and the National Natural Science Foundation of China (22136001)

Abstract: Hydrofluorocarbons (HFCs) and hydrofluoroolefins (HFOs) are mainly employed to substitute hydrochlorofluorocarbons. In order to evaluate whether the HFCs and HFOs are ideal alternatives for hydrochlorofluorocarbons or not, it is necessary to fully explore their atmospheric transformation, especially the information atmospheric persistence. To date, the quantity of second-order reaction rate constants ( k _OH ) for chemicals reacting with hydroxyl radicals (·OH), which are essential parameters to characterize the atmospheric persistence of HFCs and HFOs, cannot meet the needs of atmospheric persistence assessment for HFCs and HFOs. Therefore, it is necessary to develop a method that can predict the k _OH values efficiently. Considering the efficiency and accuracy of quantum chemical calculation, quantum chemical calculation is an important way to predict the k _OH values. However, the quantum chemistry methods used in the current research are complex, and it is urgent to screen the quantum chemistry methods that are suitable for HFCs and HFOs. In this study, suitable methods for predicting the atmospheric k _OH values of HFCs and HFOs were selected from a variety of thermodynamic parameter calculation methods and kinetics calculation methods based on the experimental data of 3 HFCs (CF ₃ CF ₂ H, CF ₃ CH ₂ CF ₃ , and CF ₃ CF ₂ (CHF) ₂ CF ₃ ) and 2 HFOs (CF ₂ CH ₂ and CF ₃ CH ₂ CF ₃ ). The research results show that by comparing the mean absolute error (MAE) between the experimental lg k _OH values and the lg k _OH values calculated by different theoretical methods, the method employing the traditional transition state theory (TST) modified with the Skodje-Truhlar tunnel effect correction coefficient( κ _S ) and combining with the density functional theory (DFT) at the M06-2X-D3/def2-TZVP//M06-2X/cc-pVDZ level has the best effect on calculating the k _OH of HFCs accurately, whose MAE was 0.17; The method employing TST method modified with Wigner transmission coefficient ( κ _W ) and combining with the M06-2X-D3/aug-cc-pVTZ//M06-2X/cc-pVDZ (MAE= 0.50) showed the best performance for calculating the k _OH values of HFOs; Both of the two methods that TST modified with the κ _W correction combine with M06-2X-D3/aug-cc-pVTZ//M06-2X/cc-pVDZ (MAE = 0.34) or M06-2X-D3/jul-cc-pVTZ//M06-2X/cc-pVDZ (MAE = 0.35) were suitable for the k _OH prediction of HFCs and HFOs. In this study, the selected methods provide efficient and accurate methods for the k _OH calculation and atmospheric persistence assessment of HFCs and HFOs.

大气中的·OH具有强氧化性和低选择性，是很多污染物氧化降解的关键物种 ^{[

6

]} ，因此污染物与·OH反应的二级反应速率常数（ k _OH , cm ³ ·molecule ⁻¹ ·s ⁻¹ ）是评价污染物大气持久性的重要参数. 传统的 k _OH 实验测定方法耗时耗力，亟待发展新的方法获取HFCs和HFOs的 k _OH . 近年来，计算机软件、硬件的飞速提升和量子化学理论的不断发展，尤其是密度泛函理论（DFT），可直接从分子结构出发实现 k _OH 从头计算. 采用适当的量子化学计算方法不仅速度快而且结果可以媲美实验值，因此有望在 k _OH 的快速获取方面发挥重要作用，从而有助于评估污染物的大气持久性. 近年来，探究·OH引发气相污染物降解的反应机制和动力学的研究逐渐增多，包括丙酸甲酯 ^{[

7

]} 、多氯联苯 ^{[

8

]} 、农药 ^{[

9

]} 等. 本研究考察了碳链长度、官能团位置等因素，选择3个HFCs：1,1,1,2-四氟乙烷（CF ₃ CFH ₂ ）、1,1,1,3,3,3-六氟丙烷（CF ₃ CH ₂ CF ₃ ）、2H,3H-十氟戊烷（C ₂ F ₅ (CHF) ₂ CF ₃ ）和2个HFOs：1,1-二氟乙烯（CF ₂ =CH ₂ ）、1H,1H,2H-十七氟-1-葵烯（CF ₃ (CF ₂ ) ₇ CH ₂ =CH ₂ ）作为模型化合物，以其 k _OH 实测值为参考，筛选适用于计算HFCs和HFOs气相 k _OH 值的量子化学方法. 将不同的方法计算所得 k _OH 与实测值进行比较，发展关于HFCs和HFOs的高准确性和适用性的 k _OH 计算方法. 由于在大气中HFCs和HFOs存在多种构象，不同构象与·OH的反应性不同，因此采用波恩奥本海默分子动力学（BOMD） ^{[

19

]} 模拟和量子化学计算相结合的方法来获得目标化合物的最稳定构象. BOMD模拟使用CP2K 8.2.0 ^{[

20

]} 软件包，NVT系综，利用Nose-Hoover控温方法将温度稳定在300 K，利用BLYPD3/DZVP-GTH方法计算5000步，步长为0.5 fs. 从模拟的动力学轨迹中选取多种能量较低的构象，然后使用M06-2X ^{[

21

]} /cc-pVDZ ^{[

22

]} 计算方法对结构进行优化，最终选取能量最低的构象作为目标化合物的最稳定构象，用来考察它与·OH的反应，最低能量构象如图1 所示. 量子化学计算在Gaussian 09 ^{[

23

]} 软件包中进行. 理论上，·OH与HFCs、HFOs可以发生夺H原子或F原子的反应，还可以在不饱和键发生·OH加成反应. 前人在研究CF ₂ =C(CH ₃ )CF ₃ 、CF ₂ =C(CH ₃ ) ₂ 、1H-七氟环戊烯与·OH的反应中发现·OH难以夺取F原子 ^{[

10

,

13

]} ，因此本研究仅考虑·OH夺取HFCs和HFOs上的H原子. 对于3个HFCs，其反应机理仅为夺取C原子上的H原子. 由于H原子的位置可能会影响·OH夺取能力，所以选择CF ₃ CFH ₂ 、CF ₃ CH ₂ CF ₃ 以及C ₂ F ₅ (CHF) ₂ CF ₃ 作为模型化合物. 考虑到CF ₃ CFH ₂ 最低构象具有 C _s 对称性，与·OH反应仅计算1条氢夺取途径. 而C ₂ F ₅ (CHF) ₂ CF ₃ 和CF ₃ CH ₂ CF ₃ 分子的最低构象不具备对称性，需考虑所有的氢夺取反应途径. 对于HFOs，·OH与其反应机理包括H夺取和·OH加成. 考虑到CF ₂ =CH ₂ 和CF ₃ (CF ₂ ) ₇ CH ₂ =CH ₂ 分子的对称性，两者与·OH反应分别考虑3条（1条氢夺取+2条·OH加成）和6条（3条氢夺取+3条·OH加成）反应途径，所有模型化合物与·OH反应的反应途径见图2 . 表1 给出了在不同方法下计算的模型化合物的 k _OH 值. 可以看出，CF ₃ CF ₂ H、 CF ₃ CH ₂ CF ₃ 、CF ₃ CF ₂ (CHF) ₂ CF ₃ 、CF ₂ CH ₂ 和CF ₃ CH ₂ CF ₃ 的 k _OH 范围分别为6.79 × 10 ⁻¹⁶ — 4.93 × 10 ⁻¹⁴ cm ³ ·molecule ⁻¹ ·s ⁻¹ 、8.47 × 10 ⁻¹⁷ — 5.99 × 10 ⁻¹⁵ cm ³ ·molecule ⁻¹ ·s ⁻¹ 、2.10 × 10 ⁻¹⁵ — 5.65 × 10 ⁻¹⁴ cm ³ ·molecule ⁻¹ ·s ⁻¹ 、4.81 × 10 ⁻¹³ — 8.90 × 10 ⁻¹¹ cm ³ ·molecule ⁻¹ ·s ⁻¹ ；7.27 × 10 ⁻¹⁴ — 1.08 × 10 ⁻¹¹ cm ³ ·molecule ⁻¹ ·s ⁻¹ . 它们对应的大气半减期范围分别为：0.40 — 29.00 a；3.29 — 232.83 a；0.34 — 9.39 a；0.08 — 14.76 d；0.65 — 97.66 d. 表明不同计算方法对HFCs和HFOs的 k _OH 值和持久性评估的影响较大. 此外，HFOs的 k _OH 值普遍大于HFCs的 k _OH 值的研究结果表明在对流层条件下，HFOs与·OH反应更快，更容易被·OH氧化去除. 表2 列出了HFCs和HFOs实测与计算的lg k _OH 平均绝对误差（MAE），当MAE值小于0.500时认为方法预测的 k _OH 的效果较好. 对于HFCs，ωB97X-D结合 κ _S 修正的TST的效果不理想（MAE的范围为0.692 — 1.003）；M06-2X-D3结合 κ _S 修正的TST方法更具优势，其MAE值均小于0.250. 其中，采用基组def2-TZVP（MAE = 0.169）、may-cc-pVTZ （MAE = 0.170）、jun-cc-pVTZ （MAE = 0.178）、def2-TZVPP （MAE = 0.182）、jul-cc-pVTZ （MAE = 0.193）和aug-cc-pVTZ （MAE = 0.197）计算方法效果更优. 因此，当计算·OH和HFCs的反应时，建议使用上述修正TST和计算单点能的方法计算HFCs的 k _OH 值. 对于HFOs，M06-2X-D3结合aug-cc-pVTZ基组计算单点能，并采用 κ _W 修正的TST计算 k _OH ，得到的lg k _OH 的MAE最小（0.497）. 因此，建议使用 κ _W 修正的TST方法结合M06-2X-D3/aug-cc-pVTZ//M06-2X/cc-pVDZ计算HFOs的 k _OH 值. 对比所有模型化合物（3个HFCs和2个HFOs）lg k _OH 的MAE值，发现M06-2X-D3和ωB97X-D泛函结合不同基组得到的lg k _OH 的MAE范围分别为0.34—0.78和0.51—1.11. κ _S 修正的TST方法结合M06-2X-D3泛函计算单点能的MAE值范围为0.34—0.50，均≤0.500. 按照MAE值排序，利用 κ _S 修正TST的动力学方法结合不同单点能计算方法中，最优的2种方法分别为结合M06-2X-D3/aug-cc-pVTZ （MAE = 0.34）和结合M06-2X-D3/jul-cc-pVTZ （MAE = 0.35）. κ _W 修正TST的动力学方法结合不同单点能计算方法中，最优的2种方法分别为结合M06-2X-D3/aug-cc-pVTZ （MAE = 0.47）和结合M06-2X-D3/jul-cc-pVTZ （MAE = 0.49）. 因此，本研究推荐 κ _S 修正的M06-2X-D3/aug-cc-pVTZ//M06-2X/cc-pVDZ或者M06-2X-D3/jul-cc-pVTZ//M06-2X/cc-pVDZ方法计算HFCs和HFOs的 k _OH . 表3 为筛选出分别适用于HCFs和HFOs的计算方法、计算得到的反应的热力学和动力学参数，其中HCFs的 ∆V 均为0 kJ·mol ⁻¹ . 对于3种HFCs，可以看出·OH 夺取HFCs上的H原子时，焓变（Δ H ）均小于0 kJ·mol ⁻¹ ，表明反应可自发进行. 然而由于Δ E 较高（12.75—23.16 kJ·mol ⁻¹ ），在298 K条件下反应很难发生. 表明HFCs可能在大气中持久存在. 此外，对比3种HFCs （CF ₃ CH ₂ F、CF ₃ CH ₂ CF ₃ 和CF ₃ CF ₂ (CHF) ₂ CF ₃ ）的 k _OH 值，可以看出碳链长度对HFCs的 k _OH 几乎没有影响. 对于2种HFOs，可以看出所有反应的Δ H 值小于0 kJ·mol ⁻¹ ，表明反应是放热反应. 而H夺取反应途径的Δ E 值明显高于加成反应，表明·OH加成反应是·OH与2种HFOs反应的主要反应通道. 对比动力学数据，CF ₂ =CH ₂ 和CF ₃ (CF ₂ ) ₇ CH ₂ =CH ₂ 双键加成的产物分支比分别为99.99%和99.96%，同样证明双键加成是主要的反应机制. 此外，双键加成（3d, 4d）和（5d, 6d）反应通道的 k _OH 值分别为3.76 × 10 ⁻¹³ cm ³ ·molecule ⁻¹ ·s ⁻¹ 和4.00 × 10 ⁻¹³ cm ³ ·molecule ⁻¹ ·s ⁻¹ ，说明—CF ₂ 和—CH ₂ 对 k _OH 的影响较小. 值得注意的是，·OH加成到CF ₃ (CF ₂ ) ₇ CH ₂ =CH ₂ 双键不同位置上时，其 k _OH 的值也有明显不同. 5e的 k _OH 为（1.74 × 10 ⁻¹³ cm ³ ·molecule ⁻¹ ·s ⁻¹ ）明显高于4e （7.76 × 10 ⁻¹⁵ cm ³ ·molecule ⁻¹ ·s ⁻¹ ）和6e （2.04 × 10 ⁻¹⁵ cm ³ ·molecule ⁻¹ ·s ⁻¹ ）反应通道. 5e反应通道的产物分支比为94.62%，这表明·OH更容易与CF ₃ (CF ₂ ) ₇ CH ₂ =CH ₂ 以5e的反应通道反应. 如图3 中4e、5e和6e的过渡态所示，·OH在加成过程中，可能受到碳链上F原子空间位阻的影响. 本研究以5个HFCs、HFOs的 k _OH 实测值作为参照，从16种单点能计算方法和2种动力学计算方法中筛选适合HFCs和HFOs的 k _OH 值的热力学和动力学参数的计算方法. 以MAE作为检验计算方法效果的标准，HFCs推荐使用 κ _S 修正TST结合M06-2X-D3/def2-TZVP//M06-2X/cc-pVDZ方法计算 k _OH ；HFOs推荐使用 κ _W 修正TST结合M06-2X-D3/aug-cc-pVTZ//M06-2X/cc-pVDZ方法计算 k _OH ；推荐使用 κ _S 修正TST方法结合的M06-2X-D3/aug-cc-pVTZ//M06-2X/cc-pVDZ或M06-2X-D3/jul-cc-pVTZ//M06-2X/cc-pVDZ方法计算HFCs、HFOs的 k _OH . 此研究筛选了适用于计算HFCs和HFOs的 k _OH 值的量子化学方法，为高效、准确预测HFCs和HFOs的 k _OH 和评估其大气持久性提供了方法支撑. Figure . Global minimum conformations of HFCs and HFOs as reference （The unit of distance is nm） Figure . Possible pathways for the reactions of CF ₃ CFH ₂ （A）, CF ₃ CH ₂ CF ₃ （B）, C ₂ F ₅ (CHF) ₂ CF ₃ （C）, CF ₂ =CH ₂ （D）, CF ₃ (CF ₂ ) ₇ CH ₂ =CH ₂ （E） with ·OH. Figure . Transition-state geometries for the reaction of ·OH with CF ₃ (CF ₂ ) ₇ CH=CH ₂ （The unit of distance is nm）

地址：北京市海淀区双清路18号京ICP备05002858号邮编：100085 电话：010-62923569 邮箱： [email protected]

北京仁和汇智信息技术有限公司开发技术支持： [email protected]

推荐文章

有腹肌的警车 · Traefik 3.x with Passbolt HTTP setup giving CORS error - Installation Issues - Passbolt community fo

1 月前

体贴的麻辣香锅 · 《影之诗》国服人气卡牌投票结果公布！ - 哔哩哔哩

1 月前

狂野的日光灯 · 2019年宁海县国民经济和社会发展统计公报

2 月前

迷茫的海龟 · GitHub - royalwang/Bob-1: Bob 是一款 Mac 端翻译软件，翻译方式支持划词翻译和截图翻译，翻译引擎支持有道翻译、百度翻译和谷歌翻译~

4 月前

一身肌肉的包子 · dotnet msbuild 命令 - .NET CLI | Microsoft Learn

6 月前

Link管理 · 51好读 · Sov5搜索 · 小百科

link管理 - 链接快照平台