Chromophoric electrons

CHROMOPHORIC ELECTRONS. Electrons in the double bonds of the chromophore groups. Such electrons are not bound as lightly as those of single bonds and can thus be transferred into higher energy levels with less expenditure of energy. Their electronic spectra appear at frequencies in the visible or near ultraviolet region of the spectrum. 

A further complication associated with the application of molecular mechanics calculations to relative stabilities is that strain energy differences correspond to A(AH) between conformers with similar chromophores (electronic effects) and an innocent environment (counter ions and solvent molecules), whereas relative stabilities are based on A(AG). The entropy term, TAS, may be calculated by partition functions,... 

Since inter chromophore electron exchange can be neglected the product of single chromophore electronic wave functions ru expansion basis. To order the CC Hamiltonian with respect to the number of basic excitations we start with the electronic ground-state... 

To compute the Coulomb matrix element, Eq. (8), we first note that the multiple integration with respect to the coordinates of all electrons of chromophore m and n can be reduced to a two-fold coordinate integration. This becomes possible because of the antisymmetric character of the chromophore electronic wave functions. Therefore, we introduce single electron densities of chromophore m ... 

The total absorption spectrum appears as the simple addition of the individual absorbance of all chromophores in the CC. The trace is reduced to the vibrational wave packet overlap in the electronic ground and excited state (averaged with respect to the chromophore electronic ground-state vibrational equilibrium, described by the density operator Rmg Hma = Tm + Uma). 

In the first contribution, Huxter Scholes present a review of the recent evolution of theory of EET in condensed phase from their earliest and simple formulation, based on the Forster theory to the most recent advances of theoretical and computational methods based on continuum solvation models. In the second contribution, Curutchet reviews the recent developments of PCM towards accurate theoretical investigations of EET in solution. In particular, the modelization of the various contributions of solvent effects in the chromophore-chromophore electronic coupling is presented using quantum-mechanical approaches. 

Fig. I. Arrangement of the chromophores, electron donors, and electron acceptors in the bacterial reaction center of Rhodobacter sphaeroides [2f], The horizontal lines at the top and bottom of the figure represent the approximate location of the surfaces of the lipid bilayer membrane...

Keywords Chromophores Electron transfer Energy transfer Excited-state chemistry Metal-organic chromophores Photoluminescence Photophysics Platinum... 

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