二芳基乙烯光致变色理论研究

Theoretical Study on Photochromism of Diaryl Ethylene

闭环全氟二芳基乙烯对光较为敏感,在紫外光照射下会发生开环反应。利用密度泛函研究了全氟二芳基乙烯光致变色的初级光化学反应机理,基态条件下,全氟代环戊烯分子由开环到闭环需克服91.48kJ/mol的势垒,反应常温下较难发生,但在激发态时只需克服21.52 kJ/mol的势垒,其逆反应活化能更小只有9.29kJ/mol,故开环及闭环反应容易发生,与实验事实相符。

Closed-ring perfluorinated diarylene is very sensitive to light and it will occur the open-ring reaction under UV light irradiation.In this paper,the primary photochemical reaction mechanism of the diarylene about phototropy using density functional theory(DFT)the reaction from the open-ring configuration turning into closed-ring configuration of the perfluorinated diarylene is difficult at room temperature due to 91.48 kJ/mol potential barrier on the ground state,however the reaction is easy due to over 21.52 kJ/mol potential barrier on the excited state,and the activation energy of the reverse of reaction is only 9.29 kJ/mol,which enable the open-ring and closed-ring reaction to become easy and the calculated results are in agreement with the experiment.