Computational Design of a Family of Light-Driven Rotary Molecular Motors with Improved Quantum Efficiency

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• 作者：Alexander Nikiforov ; Jose A. Gamez ; Walter Thiel ; Michael Filatov
• 刊名：The Journal of Physical Chemistry Letters
• 出版年：2016
• 出版时间：January 7, 2016
• 年：2016
• 卷：7
• 期：1
• 页码：105-110
• 全文大小：476K
• ISSN：1948-7185

文摘

Two new light-driven molecular rotary motors based on the N-alkylated indanylidene benzopyrrole frameworks are proposed and studied using quantum chemical calculations and nonadiabatic molecular dynamics simulations. These new motors perform pure axial rotation, and the photochemical steps of the rotary cycle are dominated by the fast bond-length-alternation motion that enables ultrafast access to the S₁/S₀ intersection. The new motors are predicted to display a quantum efficiency higher than that of the currently available synthetic all-hydrocarbon motors. Remarkably, the quantum efficiency is not governed by the topography (peaked versus sloped) of the minimum-energy conical intersection, whereas the S₁ decay time depends on the topography as well as on the energy of the intersection relative to the S₁ minimum. It is the axial chirality (helicity), rather than the point chirality, that controls the sense of rotation of the motor.