Ahmed Syed Bilal, Kan Hei Wun, Lam King-Cheong, Yip Cho-Tung
School of Science, Harbin Institute of Technology (Shenzhen) Shenzhen 518055 China
Key Laboratory of Quantitative Synthetic Biology, Shenzhen Institute of Synthetic Biology, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences Shenzhen 518055 China.
RSC Adv. 2025 Mar 17;15(10):8053-8059. doi: 10.1039/d4ra06792d. eCollection 2025 Mar 6.
Molecular motors offer promising applications in the fields of nanodevices and biological systems, as the accurate control of directional rotation at the molecular scale holds great potential. In this context, it is highly relevant to study a new class of molecular motors that can undergo isomerization. Since the first report of the chiral -alkyl imine-based motors, most investigations have focused on the unidirectional rotation process induced by light and heat. However, this work explores an alternative mechanism - the electron-induced stimulating mechanism of the molecular motor. We theoretically investigate how charge injection and extraction can influence molecular rotation. The rotation occurs around the central axle, which is measured as the torsion angle between the rotor and the stator fragments of the molecule against the C[double bond, length as m-dash]N double bond. Our computational study reveals that the introduction of charge reduces the energy barrier, facilitating more favourable molecular rotation than in the neutral singlet state. The charged molecule in a quartet spin state can rotate internally, while that in the doublet state cannot. Our findings provide a molecular scale understanding of the reaction pathways and highlight the significant role of charge in promoting the isomerization and rotational behaviour of the molecular motor.
分子马达在纳米器件和生物系统领域有着广阔的应用前景，因为在分子尺度上精确控制定向旋转具有巨大潜力。在此背景下，研究一类新型的可发生异构化的分子马达具有高度相关性。自从基于手性烷基亚胺的马达首次被报道以来，大多数研究都集中在光和热诱导的单向旋转过程上。然而，这项工作探索了一种替代机制——分子马达的电子诱导刺激机制。我们从理论上研究了电荷注入和提取如何影响分子旋转。旋转围绕中心轴发生，该中心轴通过分子的转子和定子片段相对于C=N双键的扭转角来测量。我们的计算研究表明，电荷的引入降低了能垒，与中性单重态相比，更有利于分子旋转。处于四重自旋态的带电分子可以内部旋转，而处于双重态的带电分子则不能。我们的研究结果提供了对反应途径的分子尺度理解，并突出了电荷在促进分子马达异构化和旋转行为方面的重要作用。
