Continuum vs. atomistic approaches to computational spectroscopy of solvated systems

Molecular spectral signals can be significantly altered by solvent effects. Among the many theoretical approaches to this problem, continuum and atomistic solvation models have emerged as the most effective for properly describing solvent effects on the spectroscopic signal. In this feature article, we review the continuum and atomistic descriptions as applied to the calculation of molecular spectra, by detailing the similarities and differences between the two approaches from the formal point of view and by analyzing their advantages and disadvantages from the computational point of view. Various spectral signals, of increasing complexity, are considered and illustrative examples, selected to exacerbate the differences between the two approaches, are discussed.