Bag Sampad, Chandra Sankhabrata, Bhattacharya Atanu
Department of Inorganic and Physical Chemistry, Indian Institute of Science, Bangalore, India.
Phys Chem Chem Phys. 2017 Oct 11;19(39):26679-26696. doi: 10.1039/c7cp03738d.
Molecular attosecond science has already started contributing to our fundamental understanding of ultrafast purely electron dynamics in isolated molecules under vacuum. Extending attosecond science to the liquid phase is expected to offer new insight into the influence of a surrounding solvent environment on the attosecond electron dynamics in solvated molecules. A systematic theoretical investigation of the attochemistry of solvated molecules would help one design attosecond experiments under ambient conditions to explore the attochemistry in a liquid environment. With this goal in mind, for the first time, we have explored the attochemistry of molecules surrounded by different non-polar solvent environments. For this work, we have focused on the attosecond charge conduction through gold-thiolate and gold-selenolate linkages following the vertical ionization of the S/Se(CH)-CH-phenyl-X unit anchored to a gold dimeric cluster (Au), where X represents either a strong electron donating N(CH) group or a strong electron withdrawing NO group. To model solvation effects on the attochemistry of molecules containing gold-chalcogen linkages, we have used an implicit solvent model (Polarizable Continuum Model) under the density functional theory (DFT) formalism for non-polar solvents. We have found that the charge migration time scale in molecules becomes faster in the presence of the solvent environment as compared to that under vacuum. Charge oscillation does not damp quickly in molecules surrounded by the solvent environment as compared to that under vacuum. Furthermore, the direction of the charge migration may change in molecules when they are surrounded by the solvent environment as compared to that under vacuum. Thus, the present work has laid the foundation, for the first time, for thinking of the attochemistry into the realm of liquids.
分子阿秒科学已经开始有助于我们对真空中孤立分子中超快纯电子动力学的基本理解。将阿秒科学扩展到液相有望为周围溶剂环境对溶剂化分子中阿秒电子动力学的影响提供新的见解。对溶剂化分子的阿秒化学进行系统的理论研究将有助于人们在环境条件下设计阿秒实验，以探索液体环境中的阿秒化学。出于这个目标，我们首次探索了被不同非极性溶剂环境包围的分子的阿秒化学。对于这项工作，我们关注的是在锚定到金二聚体簇（Au）上的S/Se(CH)-CH-苯基-X单元垂直电离后，通过金硫醇盐和金硒醇盐键的阿秒电荷传导，其中X代表强给电子N(CH)基团或强吸电子NO基团。为了模拟溶剂化对含金硫属键分子的阿秒化学的影响，我们在非极性溶剂的密度泛函理论（DFT）形式下使用了隐式溶剂模型（极化连续介质模型）。我们发现，与真空相比，在溶剂环境存在的情况下，分子中的电荷迁移时间尺度变得更快。与真空相比，在被溶剂环境包围的分子中，电荷振荡不会很快衰减。此外，与真空相比，当分子被溶剂环境包围时，电荷迁移的方向可能会改变。因此，本工作首次为将阿秒化学引入液体领域奠定了基础。
