0000000000547771
AUTHOR
Karsten Elich
Quantitative interpretation of the red edge excitation (REE) effect of 9,9′-bianthryl in polyisobutene by band shape analysis of the temperature-dependent optical fluorescence spectra
Optical fluorescence spectra of 9,9′-bianthryl (BA) in polyisobutene (PIB) were measured as a function of the excitation wavelength at various temperatures between 210 and 293 K. Irradiation at the red edge of the absorption spectra selectively excites distinct conformers with respect to the torsional angle. This leads to a strong dependence of the vibronic band shape of the fluorescence spectra on the excitation wavelength. The marked temperature dependence of the band shape may be attributed to the viscosity-dependent deceleration of the torsional relaxation of BA in the highly viscous polymer which prevents the excited state ensemble from reaching thermal equilibrium. The predominant bro…
Effect of S1 Torsional Dynamics on the Time-Resolved Fluorescence Spectra of 9,9‘-Bianthryl in Solution
Time-resolved fluorescence spectra of 9,9‘-bianthryl (BA) were measured in methylcyclohexane (MCH) and a Decalin−isooctane (D−ISOO) mixture at several temperatures between 127 and 200 K. A suitable...
The use of simulation methods to obtain the structure and conformation of 10-cyano-9,9′-bianthryl by electron diffraction and high-resolution imaging
Abstract Experimental electron diffraction patterns and high-resolution images were used to determine the space group and unit cell dimensions of 10-cyano-9,9′-bianthryl. Subsequently the molecular conformation was calculated by semi-empirical quantum-mechanical methods. The molecule was then placed with the appropriate symmetry into the unit cell and the conformational as well as the packing energy deduced by an iterative procedure until good agreement was obtained between experiment and theory.