Optical spectra of molecular aggregates and crystals: testing approximation schemes
نویسندگان
چکیده
منابع مشابه
Intrinsic optical bistability of thin films of linear molecular aggregates: the one-exciton approximation.
We perform a theoretical study of the nonlinear optical response of an ultrathin film consisting of oriented linear aggregates. A single aggregate is described by a Frenkel exciton Hamiltonian with uncorrelated on-site disorder. The exciton wave functions and energies are found exactly by numerically diagonalizing the Hamiltonian. The principal restriction we impose is that only the optical tra...
متن کاملIntrinsic optical bistability of thin films of linear molecular aggregates: the two-exciton approximation.
We generalize our recent work on the optical bistability of thin films of molecular aggregates [J. A. Klugkist et al., J. Chem. Phys. 127, 164705 (2007)] by accounting for the optical transitions from the one-exciton manifold to the two-exciton manifold as well as the exciton-exciton annihilation of the two-exciton states via a high-lying molecular vibronic term. We also include the relaxation ...
متن کاملMultisite structure of optical spectra of activators in garnet crystals
The analysis of selective excitation and emission spectra of l'm3' in YAG and GGG laser systems is presented. The observed multisite structure is assigned to non-stoichiometric defects. Up to six centers are separated, with complex spectra connected with lowering of the local symmetry.
متن کاملStructure Prediction of Self-Assembled Dye Aggregates from Cryogenic Transmission Electron Microscopy, Molecular Mechanics, and Theory of Optical Spectra
Cryogenic transmission electron microscopy (cryo-TEM) studies suggest that TTBC molecules self-assemble in aqueous solution to form single-walled tubes with a diameter of about 35 Å. In order to reveal the arrangement and mutual orientations of the individual molecules in the tube, we combine information from crystal structure data of this dye with a calculation of linear absorbance and linear ...
متن کاملOptical properties and transformation mechanism of oxygen centres and their aggregates in CaF2 crystals
Oxygen-vacancy dipoles and dimers in CaF2 crystals have been studied ab initio at DFT level and with the shell model using pair potentials. The calculated dipole reorientation barrier is 0.64 eV and the activation energy for diffusion of the dipoles is 1.61 eV. Optical absorption of O2--VA dipole have been calculated with TD DFT and identified with experimental absorption bands, which appeared ...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
ژورنال
عنوان ژورنال: Physical Chemistry Chemical Physics
سال: 2019
ISSN: 1463-9076,1463-9084
DOI: 10.1039/c9cp03122g