Trans-scale crystal dynamics for controlling kinetic responses in organic molecular systems

Area of Science:

• Solid-state chemistry
• Materials science
• Photochemistry

Background:

• Controlling material dynamics in single crystals is crucial for understanding functional systems.
• Visualizing rapid chemical and structural changes in situ remains a significant challenge.

Purpose of the Study:

• To develop a molecular crystal platform for dual physical control of solid-state [4+4] photocycloaddition.
• To enable tunable and observable crystal dynamics through combined thermal and light stimuli.

Main Methods:

• Utilized chemically engineered 1,8-bis(pentafluorophenyl)anthracene single crystals.
• Employed visible-light irradiation and temperature control for dual physical stimuli.
• Observed reaction dynamics under various light sources (UV, LED, laser, sunlight).

Main Results:

• Demonstrated dual controllability of [4+4] photocycloaddition by heat and light.
• Observed thermally switchable reaction states controlled by lattice strain.
• Identified reaction kinetics dependence on light propagation and molecular orientation, revealing anisotropic photodynamic control.

Conclusions:

• Established a general strategy for tunable and observable crystal dynamics via molecular packing design and photo-thermal science.
• The trans-scale approach integrates chemical design, photo-thermal science, and anisotropic parameters.
• Weak light irradiation allows direct observation of intermediate states and correlation with lattice strain.