Time：25th Nov., 2019, 2:00 pm
Venue：Energy Building A
Lecturer：Prof. Julien Bloino, Scuola Normale Superiore
Computational spectroscopy is nowadays routinely used as a predictive and interpretative tool to complement and support experiment, providing insights of the underlying elementary phenomena responsible for the overall band-shape. However, the reliability of the produced results is strongly correlated to the underlying models.
This aspect can be especially critical in some fields of applications like chiroptical analysis, for instance. Such considerations emphasize the need of carefully setting up computational protocols, in particularbyselecting the most appropriate level of theory available. As a matter of fact, for medium-to-large molecular systems with possible environmental effects, a trade-off is necessary between accuracy and computational cost, and several strategies can be devised, with suitability varying depending on the cases.
To facilitate the setup of the most efficient and reliable route for the simulation of accurate spectra, we have been developinga versatile and modular platform, called virtual spectrometer. Its main features are the possibility to apply anharmonic corrections on vibrational spectra and include vibrational contributions to electronic spectra. Such capabilities offer a level of accuracy beyond the methods stillcommonly used to simulate vibrational and electronic spectra, even for medium-large molecules containing several tens of atoms. With the aim of providing an easy-to-use tool, able to provide accurate results, it is necessary to properly identify and possibly overcome the shortcomings in the approximations adopted by the basic models on which it relies.
The potential impact of such issues, like resonances in VPT2 calculations or molecular deformations and mode mixing upon electronic transition, and strategies to ensure the reliability and accuracy of the results will be discussed. Those aspects, as well as current projects, will be illustrated with case studies involving different spectroscopies,with emphasis on chiroptical ones, with possible account of experimental conditions, like mixtures, environment or temperature.
Julien Bloino is an associate professor in Physical Chemistry at Scuola Normale Superiore in Pisa, Italy. He received his chemical engineering degree and M.Sc. degree from Chimie ParisTech, France, and his Ph.D. degree in Physical Chemistry from University of Naples, Italy. His research interests are the development and application of models for the simulation of vibrational and electronic spectra forchiral molecular systems and molecules of astrochemical interest. The theoretical models are primarily focused on the proper description of nuclear motions, in particular vibrations. He is an active contributor to the Gaussian suite of quantum chemical programs.
Contact: NIU Peilin, Group 503