Interchain interaction in a prototypical conjugated oligomer from polarized absorption at 4.2 K: α-sexithienyl single crystal

Abstract

Rigorous Franck-Condon absorption and emission spectra of conjugated oligomers from quantum chemistry

Absorption and Emission in Quaterthienyl Thin Films

“…Recently, Weiser and Moller [24] measured a strong increase in reflectivity approximately 1.1 eV above the band origin in aT6 crystals in satisfactory agreement with our calculations. We stress that the calculated DS value is much larger than that reported previously by some authors; [4,5] the model used here is, however, more relevant for the description of the optical properties of the crystal, since all important interactions were included [6] and the size of the aggregates was sufficiently large. The smaller estimates of 2900 cm ±1 for aT4 (and 2600 cm ±1 in aT6) [4,5] from polarized absorption measurements on single crystals (with k normal to the herringbone plane) [25] are likely due to mistaking the peak A 2 for the upper Davydov component, a point originally raised by Petelenz and Andrzejak.…”

“…Many methods for the synthesis of inorganic nanotubes have been based on high-temperature processes. These include chemical vapor transport, [4] sol±gel process, [5] arc-discharge, [6] solvothermal treatment, [7] and oxide nanowhisker growth. [8] Low-temperature routes such as templated synthesis have also been attempted, [9,10] but it has proved difficult to form single-crystalline nanotubes.…”

Analysis of the vibronic fine structure in circularly polarized emission spectra from chiral molecular aggregates

“…Upon aggregation, photophysical properties of the aggregates change drastically, which is in many cases interpreted in terms of formation of a band of exciton states with a width on the order of 10 3 cm Ϫ1 . 43 These numbers indicate that the intermediate coupling regime is expected to apply for aggregates of -conjugated oligomers, and a reduction of the absolute value of g lum with decreasing photon energy is predicted. Experiments on a model compound containing two terthiophene chromophoric units indeed showed strong reduction of ͉g lum ͉ with increasing wavelength of fluorescence detection.…”

Single‐Crystalline Scroll‐Type Nanotube Arrays of Copper Hydroxide Synthesized at Room Temperature

“…These include chemical vapor transport, [4] sol±gel process, [5] arc-discharge, [6] solvothermal treatment, [7] and oxide nanowhisker growth. [8] Low-temperature routes such as templated synthesis have also been attempted, [9,10] but it has proved difficult to form single-crystalline nanotubes.…”