Deformation density electronic excited state

When dealing with the modification induced on the UV/ VIS spectra of a chromophore embedded in a macromo-lecular environment, one has to take into account three main effects the geometric deformation induced by the rather rigid environment, the electrostatic effect modeled by the polarization of the wavefunction induced by the MM point charges, and finally the electronic polarization of the environment due to the modification of the electronic density of the environment to adapt itself to the new excited state electronic density. 

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