半花菁类非绝热紫外保护机理的超快光谱研究  

Ultrafast Spectroscopic Study on Non-adiabatic UV Protection Mechanism of Hemicyanines

作　　者：张明水 楚亚 吴子博 郭玉荣 史亚男 王朝 王孟琪 钟瑛倩 张皓月 王雅楠 王俊[2] 赵广久 Ming-shui Zhang;Ya Chu;Zibo Wu;Yu-rong Guo;Ya-nan Shi;Chao Wang;Meng-qi Wang;Ying-qian Zhong;Hao-yue Zhang;Ya-nan Wang;Jun Wang;Guang-jiu Zhao(Tianjin Key Laboratory of Molecular Optoelectronic Sciences,Department of Chemistry,School of Science,Tianjin University,Tianjin 300354,China;College of Chemistry and Chemical Engineering,Northeast Petroleum University,Daqing 163318,China)

机构地区：[1]天津大学理学院化学系分子光电子科学重点实验室,天津300354 [2]东北石油大学化学化工学院,大庆163318

出　　处：《Chinese Journal of Chemical Physics》2023年第1期25-34,I0001,共11页化学物理学报（英文）

基　　金：This work was supported by the National Natural Science Foundation of China(No.21873068,No.21573229 and No.21422309).

摘　　要：本文首次结合理论计算与瞬态吸收光谱,阐明了典型的半花菁类化合物Hemicy和Dhemicy的紫外光防护动力学机理.理论和实验证明,Hemicy和Dhemicy在UVC、UVB和UVA区域都有很强的吸收能力.Hemicy和Dhemicy吸收能量后跃迁到激发态Hemicy和Dhemicy在S_(1)态和S_(0)态势能曲线的圆锥交点处,经历从S_(1)态到S_(0)态的非绝热弛豫和顺式反异构化光物理过程.瞬态吸收光谱表明反式-顺式光异构化过程将在几皮秒内发生.因此,通过非绝热反式-顺式光异构化过程快速地弛豫掉Hemicy和Dhemicy吸收的能量.In this work,we rstly elucidated the ultra-violet light protection dynamics mechanism of the typical hemicyanines,i.e.Hemicy and DHemicy,by combining the theoretical cal-culation method and the transient absorp-tion spectra.It is theoretically and exper-imentally demonstrated that both Hemicy and DHemicy have strong absorption in UVC(200􀀀280 nm),UVB(280􀀀300 nm),and UVA(320􀀀400 nm)regions.More-over,after absorbing energy,Hemicy and DHemicy can jump into the excited states.Subsequently,Hemicy and DHemicy relax to S_(0)states from S_(1)states rapidly by the non-adiabatic transition at the conical intersection point between the potential energy curves of S_(1)and S_(0)states,and are accompanied by the trans-cis photoisomerism.The transient absorption spectra show that trans-cis photoisomerization occur within a few picoseconds.Thus,the ultraviolet energy absorbed by Hemicy and DHemicy could be relaxed ultrafastly by the non-adiabatic trans-cis photoisomerization processes.

关 键 词：半花菁 紫外光吸收剂 势能面 非绝热 顺反式光异构化 

分 类 号：O641.1[理学—物理化学]