Environmental Effects in Computational Chemistry: Accuracy and Interpretations.

Spectroscopic techniques are valuable tools for understandingthe structure and dynamics of complex systems, such as biomolecules or nanomaterials. Most of the current research is devotedto the development of new experimental techniques forimproving the intrinsic resolution of different spectra. However,the subtle interplay of several different effects acting at differentlength and time scales still makes the interpretation andanalysis of such spectra a very difficult task. In this respect,computational spectroscopy is becoming a needful and versatiletool for the assignment and interpretation of experimentalspectra. It is in fact possible nowadays to model with relativelyhigh accuracy the physical–chemical properties of complexmolecules in different environments, and to link spectroscopicevidence directly to the structural and dynamical properties ofoptically or magnetically active solvated probes. In this Review,significant steps toward the simulation of entire spectra in condensedphases are presented together with some basic aspectsof computational spectroscopy, which highlight how intramolecularand intermolecular degrees of freedom influenceseveral spectroscopic parameters.