What is the Bond Dissociation Energy of the Vanadium Hydride Cation?
What is the Bond Dissociation Energy of the Vanadium Hydride Cation?
复制标题
氢化钒阳离子的键解离能是多少？
DOI：
10.1021/acs.jpca.0c04517
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发表时间：
2020
期刊：
影响因子：
--
通讯作者：
Ng, Cheuk-Yiu
中科院分区：
文献类型：
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作者：
Armentrout, P. B.;Chang, Yih-Chung;Ng, Cheuk-Yiu
最近的电子状态选择测量原子钒阳离子与D2和CO2的反应进行重新分析，以适当占反应物中性的动能分布。本工作通过将D2数据与之前在早期实验中获得但未发表的数据进行比较，证明了这一点的必要性。它示出，早期的数据，它利用了表面电离源的V+，V+（a5D2）和状态选择的数据基本上是相同的阈值区域，它们重叠。两个实验中V+的电子态能量和动能分布的差异非常小，并且比中性反应物的动能分布小得多，这在两个实验中是相同的。结果表明，适当占后者的分布改变的结论，关于阈值能量的吸热形成的VD+，使最近的结论，关于VD+的键能被大幅改变，并发现重现原始键能的测定。考虑到所有实验，D0（VH+）的修正最佳值为2.07 ± 0.09 eV [或D0（VD+）= 2.10 ± 0.09 eV]。这一结论得到了高水平从头计算的验证。V++ D2反应在较高的能量（以上的产品离子的解离发病）的新的和旧的数据集的差异进行了讨论。同样的方法，然后适用于最近的研究状态选择V++ CO2反应。
Recent electronic state-selected measurements of the reactions of atomic vanadium cations with D2and CO2are reanalyzed to properly account for the kinetic energy distribution of the reactant neutrals. The need for this is demonstrated in the present work by comparing the D2data to that obtained previously in earlier experiments but unpublished. It is shown that the earlier data, which utilized a surface ionization source of V+, and the state-selected data for V+(a5D2) are essentially identical in the threshold regions where they overlap. Differences in the electronic state energies and kinetic energy distributions of V+in the two experiments are very small and much smaller than the kinetic energy distribution of the neutral reactant, which is identical in both experiments. It is shown that properly accounting for the latter distribution alters the conclusions regarding the threshold energy for the endothermic formation of VD+such that recent conclusions regarding the bond energy of VD+are substantially altered and found to reproduce the original bond energy determination. Accounting for all experiments, a revised best value for D0(VH+) is 2.07 ± 0.09 eV [or D0(VD+) = 2.10 ± 0.09 eV]. This conclusion is validated by high-level ab initio calculations. Differences in the new and older data sets for the V++ D2reaction at higher energies (above the onset for dissociation of the product ion) are also discussed. The same methodology is then applied to recent studies on the state-selected V++ CO2reaction.