Photochromism of Diarylethene Molecules and Crystals: Memories, Switches, and Actuators

The crystal structure of 1,2-bis[2-methyl-5-(3-cyanophenyl)-3-thienyl]-3,3,4,4,5,5-hexafluoro-cyclopent-1-ene, C29H16F6N2S2

“…In the past decades, scientists have been paying much attention to the design and fabrication of functional photochromic compounds, such as photochromic diarylethene derivatives [5], spiropyran devatives [6] and azobenzene derivatives [7]. Among all these photochromic compounds, diarylethene derivatives are regarded as the best promising candidates for their notable thermal irreversible photochromic behaviour and remarkable fatigue resistance [4,8].…”

“…The photochromic properties of diarylethene can be strongly influenced by introducing substituents to the aryl groups, e.g. by intriducing long π conjugation or chosing appropriate electron-donating/withdrawing substituents [5,9]. In order to investigate the effect of the cyanophenyl group on the photochemical properties, we have now determined the structure of 1,2-bis[2-methyl-5-(3-cyanophenyl)-3-thienyl]-3,3,4,4,5,5-hexafluorocyclopent-1-ene.…”

Crystal structure of photochromic 1-(2-methyl-5-phenyl-3-thienyl-2-[2-methyl-5-(4-ethoxylphenyl)-3-thienyl] 3,3,4,4,5,5-hexafluoro-cyclopent-1-ene, C29H22F6OS2

“…Photochormic compounds have been attracted interest due to their promising wide applications in photonic devices, such as optical memory media, full-color display and various photoswitching devices [3]. Among various photochromic compounds, diarylethenes are promising candidates for such applications due to their excellent thermal stability of both isomers, fatigue-resistant property, high sensitivity, rapid response, and reactivity in solid state [4]. On one hand, the photochromic properties of diarylethene is strongly in uenced by the substituents at the terminal groups at the aryl moieties [4].…”

“…Among various photochromic compounds, diarylethenes are promising candidates for such applications due to their excellent thermal stability of both isomers, fatigue-resistant property, high sensitivity, rapid response, and reactivity in solid state [4]. On one hand, the photochromic properties of diarylethene is strongly in uenced by the substituents at the terminal groups at the aryl moieties [4]. Recently we have reported the photochromic diarylethene bearing di erent group, such as uorine, chlorine, methoxy and methyl [5][6][7].…”

“…In the cyclopentene ring, the two thiophene rings are linked by the C14=C18 double bond 1.352(2) Å. The two methyl groups are located on di erent sides of the C14=C18 double bond and this con guration is crucial to allow the compound to exhibit photochromic and photoinduced properties [4]. This geometry allows the breaking of the central hexa uorocyclopentene C=C double bond to form a new C-C single bond and the molecule thus can undergo a phototransition.…”