Dipartimento di Chimica

Paola D'Angelo ha il piacere di invitarvi al seminario:

Theoretical Studies of Chemical Reactivity: Kinetics and Dynamics

di  Riccardo Spezia, Sorbonne Université, Paris, France

 

Il seminario avrà luogo mercoledì 17 aprile alle ore 14 in Aula II, edificio Cagliotti (CU032). 

 

Abstract

In this seminar, we will present recent theoretical advances in studying the fundamental processes related to chemical reactivity. In particular, we will distinguish between approaches based on kinetics theory and how/when dynamical effects can modify the outcomes of kinetic theories. In particular, RRKM and Transition State Theories will be discussed and deviations from that examined. RRKM theory is typically used in the context of gas phase chemistry, and it can be used from molecular information as well as from chemical dynamics simulations. Deviations from this theory regard mainly non-equilibration of the reactant state and non-trivial post transition state dynamics. Chemical dynamics simulations are able to identify such effects leading to a better interpretation of experimental data. Transition State Theory has its ground in the canonical ensemble, which is the typical choice for solution chemistry. Direct dynamics can be used to confirm some of the assumptions of the theory and, eventually, to add corrections. In particular, a combined use of enhanced sampling methods (like Umbrella Sampling) and direct dynamics can shed light to the interplay between kinetics and dynamics. Finally, we will show the importance of considering nuclear quantum effects when studying reaction dynamics. At this end, we will discuss the use of Path Integral based molecular dynamics simulations.

References

1. A.Martin-Somer, M.Yanez, M.-P.Gaigeot and R.Spezia. J. Phys. Chem. A 118, 10882-10893 (2014).

2. A.Martin-Somer, M.Yanez, W.L.Hase, M.-P.Gaigeot and R.Spezia. J. Chem. Theory Comput. 12, 974- 982 (2016).

3. R.Spezia, A.Martin-Somer, V.Macaluso, Z.Homayoon, S.Pratihar and W.L.Hase. Faraday Discuss. 195, 599–618 (2016).

4. A.Martin-Somer, R.Spezia and M.Yanez. Phil. Trans. A 375, 20160196 (2017).

5. Y.Jeanvoine and R.Spezia. Theor. Chem. Acc. 138, 1 (2019).

6. A.Malik, R.Spezia and W.L.Hase. J. Am. Soc. Mass Spectrom. 32, 169-179 (2021).

7. A.F. Perez-Mellor and R. Spezia. J. Chem. Phys. 155, 124103 (2021).

8. F.Angiolari, S.Huppert and R.Spezia. Phys. Chem. Chem. Phys. 24, 29357-29370 (2022).

9. F.Angiolari, S.Huppert, F.Pietrucci and R.Spezia. J. Phys. Chem. Lett. 14, 5102–5108 (2023).

10. F.Angiolari, G.Mandelli, S.Huppert, C.Aieta and R.Spezia. Submitted. Preprint on ChemRXiv: https://10.26434/chemrxiv2024-wb68d.

 

Biography Prof. Riccardo Spezia

Riccardo Spezia graduated in chemistry at Università di Roma “La Sapienza” in 2000 and then got a PhD in theoretical physical chemistry in 2004 under the supervision of prof. A.Di Nola. He then moved as post-doctoral associate at Ecole Normale Supérieure in Paris in the group of prof. J.T.Hynes and then to University of Evry where we was enrolled as CNRS researcher in 2006 and got his habilitation in directing research in 2012. In 2017 he moved to Sorbonne Université in the Laboratoire de Chimie Théorique as CNRS research director (equivalent to research professor). He is actually head of the group “Reaction Dynamics” and since 2022 he is director of the CECAM-FR-MOSER node in Maison de la Simulation (Saclay). He was invited professor at Universidad de Valladolid, Spain in 2017 and at Università di Roma “La Sapienza” in 2022. His research interests are in the broad field of reaction dynamics in gas and liquid phases using theoretical methods. In particular he developed a method based on chemical dynamics trajectories to predict and understand tandem mass spectrometry of complex biomolecules. Recently, he is interested in using Path Integral based methods to chemical problems, like Resonance Raman spectroscopy, reaction rate constants and matter under vibrational strong coupling. He is the author of more than 130 articles, one book and supervised/co-supervised 12 PhD students, more than 20 internships (from bachelor to master) and 7 post-doctoral associates.