Vertical electronic excitation with a dielectric continuum model of solvation including volume polarization. II. Implementation and applications

A practical implementation is described for calculation of solute vertical electronic excitation with a new dielectric continuum model of solvation. Particular attention is given to the specific aspects associated with quantum mechanical treatment of the solute, which leads to volume polarization effects arising from penetration of the solute charge density outside the cavity nominally enclosing it. Some representative computations are presented using this method and several other related methods from the literature for the lowest vertical transitions of an acetone and a water molecule in dielectric continuum models of aqueous solution. These illustrate the two possible extreme behaviors wherein the acetone transition is found to be little affected by volume polarization, while the water transition is found to be quite sensitive to volume polarization, the latter so much so that approximate treatments of volume polarization are inadequate.