Fatigue and photochromism S1 excited state reactivity of diarylethenes from QTAIM and the stress tensor. Issue 13 (7th December 2017)

• Record Type: Journal Article
• Authors: Yang, Ping; Xu, Tianlv; Momen, Roya; Azizi, Alireza; Kirk, Steven R.; Jenkins, Samantha
• Is Part Of: International journal of quantum chemistry. Volume 118:Issue 13(2018)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2017-12-07
• Subjects: diarylethenes -- photochromism -- QTAIM -- stress tensor; Quantum chemistry -- Periodicals; 541.28
• DOI: 10.1002/qua.25565
• Languages: English
• ISSNs: 0020-7608

Abstract

Abstract: The realization of technologically relevant functional systems from idealized photochromic compounds remains elusive due to the double requirement that such switches must possess both highly efficient photo‐isomerization reactivity and extremely low fatigue over a large number of switching cycles. Nowadays, improvements of the switching properties in complex diarylethene structures are mainly attained on a "trial and error" basis through chemical substitutions aimed at tuning the chemical properties of the core of the diarylethene. Therefore, we present new guiding principles to analyze the first excited state reactivity of diarylethenes based on the quantum theory of atoms in molecules (QTAIM) including the stress tensor. This approach straightforwardly provides consistent theoretical justification to partner the already successful symmetric substitution patterns obtained from experiments. The guiding principles provided by QTAIM and stress tensor suggest more complex asymmetric patterns should be included for the systematic design of new technologically relevant functional compounds. The stress tensor trajectory Tσ ( s ) analysis is used to characterize the photochromism reaction as reusable and the fatigue reaction as irreversible and find candidate sites for alteration by future experiment. Abstract : The realization of technologically functional switches remains elusive due to such systems having to possess both highly efficient photo‐isomerization reactivity and extremely low fatigue over a large number of switching cycles. Currently, chemical substitutions, to tune chemical properties, are only on a "trial and error" basis. The fatigue behavior is displayed in the linear Tσ ( s ) of the f pathway. Possible sites for substitution are provided by inspection of the tabulated lengths Lσ of the Tσ ( s ).