ChemInform Abstract: The Photophysics and Photochemistry of α,ω‐Diphenylpolyene Singlet States

Intense Long-Lived Fluorescence of 1,6-Diphenyl-1,3,5-Hexatriene: Emission from the S<sub>1</sub>-State Competes with Formation of O<sub>2</sub> Contact Charge Transfer Complex

“…1,6-Diphenyl-1,3,5-hexatriene in cyclohexane shows strong absorption in the region of 300 -380 nm [11,21,31]. The excitation wavelength used for our transient fluorescence measurements (355 nm) is near to the absorption maximum of DPH at 353 nm.…”

Donor-Acceptor Conjugated Linear Polyenes: A Study of Excited State Intramolecular Charge Transfer, Photoisomerization and Fluorescence Probe Properties

“…The Fig. 4 Chemical structure of donor-acceptor ethenylindoles (11)(12)(13)(14)(15). Compounds 12-13 fluoresce from CRICT state.…”

“…1 (n, π*), 1 A g * (π, π*, dipole forbidden transition) and 1 B u * (π, π*, strongly allowed transition). The energy levels of these states are dependent upon the factors like (i) nature of surrounding environment like polar, non-polar or hydrogen bonding solvents, (ii) polyene chain geometry, and (iii) nature of functional group at the end of the polyene chain [11,12,21]. The transition (absorption or fluorescence) between 1 occur, leading to either internal conversion to the ground state or intersystem crossing to the ground state via a triplet excited state.…”

“…[6][7][8][9][10]. In order to understand the exact nature of the electronically excited state properties of linear polyenes, donor-acceptor molecules based on α,ω-diphenylpolyene [Ar(CH = CH) n Ar] framework, like 1,2-diphenylethene [Ar(CH = CH)Ar, DPE, stilbene], 1,4-diphenylbutadiene [Ar(CH = CH) 2 Ar, DPB], 1,6-diphenylhexatriene [Ar(CH = CH) 3 Ar, DPH] and other longer homologues have been extensively studied as models of photobiologically significant linear polyenes like retinal, carotenoids and their lower homologues [11][12][13][14][15][16][17][18][19][20]. In contrast to the non-fluorescent retinyl polyenes, the fluorescent nature of model α,ω-diphenylpolyenes facilitates study of the electronically excited state properties of linear polyenes.…”

Development of Bacteriorhodopsin Analogues and Studies of Charge Separated Excited States in the Photoprocesses of Linear Polyenes†

“…Based on the results obtained from the photochemical and photophysical studies of model systems like diphenylpolyenes, the role of conformationally and configurationally relaxed intramolecular charge‐transfer excited states has been discussed. Many excellent reviews are available on the subject (83–91).…”