Site-dependent vibronic line widths and relaxation in the mixed molecular crystal pentacene in p-terphenyl

Singlet fission in linear chains of molecules

“…The vibrationally excited states in crystalline organic materials are broadened by depopulation and dephasing processes [66][67][68] and the typical vibrational broadening for polyacenes is of the order of ~0.25-0.40meV. [69][70][71][72] The FGR is not valid when the vibrational energy level spacing is larger than the broadening of the final levels, a condition that needs to be verified for the problem under study.…”

Standard molar enthalpies of formation and of sublimation of the terphenyl isomers

“…Some of these terphenyl derivatives have quite relevant biological activities, behaving as immune suppressants, antioxidants, neuroprotectives, cytotoxic, anti-thrombosis and anticoagulants [1]. Terphenyls have been the object of extensive research over the years, enhancing their characteristics and applications such as, the ability to form polyphenylene conducting polymers [2][3][4][5], use in organic light emitting diodes (OLEDs), field-effect transistors (FETs) and nonlinear optical devices [6][7][8][9], usage as ultraviolet organic lasers [10], host organic material for dopants [11][12][13][14][15][16], in catalysis [17,18], enzyme simulation [19], metal-organic frameworks [20] and modelling glass forming systems [3,21,22]. These vast applications require the knowledge of the energetics involving these polyphenyl oligomers as well as its relation with their structures.…”

Coherence from fluorescence correlations: Oscillatory femtosecond fluorescence in pentacene/p-terphenyl

“…It shows narrow and well-separated transitions in high-resolution absorption spectroscopy at low phonon temperatures. 19,20 Because of a special type of discrete energy disorder in the mixed crystal below 190 K, the longwavelength S 1 ϭ0 ←S 0 ϭ0 transition ( 1 L a ← 1 A) splits into four absorption lines at 16 883, 16 887, 17 006, and 17064 cm Ϫ1 labeled as O1, O2, O3, and O4, respectively, and shown in Fig. 1.…”

“…͑9͒ to be of equal size for each of the site transition profiles,T 2 *Ϸ 1/T ik 2 ϭ 1/T k 2 ϩ 1/T i 2 Ӎ 2/T 2 2 , data analysis yields a best fit, single-Gaussian, inhomogeneous dephasing time T 2 *Ӎ12 ps corresponding to broadening of 2.35Ӎ33 GHz, which nicely recovers some average value of inhomogeneous broadening as obtainable by conventional, high-resolution spectroscopy. 20,21 In Fig. 6͑a͒ another set of COIN interferograms has been accumulated by independent measurements over an extended time scale of 20 ps ͓cf.…”