Advanced Computational Modeling of Catalytic Properties of Porous Materials

Samenvatting

This project aims at applying advanced quantum chemical modeling techniques to studying catalytic systems relevant to catalytic processes such as selective methane oxidation and biomass valorization. These processes are proposed to be crucial components of future and more sustainable chemical industry. The theoretical outcomes of this project are expected to aid to our understanding of these catalytic systems and provide input for the design of novel catalytic systems. This application includes 3 sub-projects focused on ab initio dynamics and post-HF studies of zeolite-catalyzed reactions. The focus is on applying advanced computational techniques such as ab initio meta-Dynamics (MTD) [Laio and Parrinello, Proc. Natl. Acad. Sci., 99 (2002) 12562] and Complete Active Space Second Order Perturbation Theory (CASPT2) method [Pulay, Int. J. Quantum. Chem., 111 (2011) 3273]. These methods will be used to get insight into the role of factors such as dynamics-induced reactivity and spin-crossing phenomena on catalytic mechanisms that are not accessible using conventional DFT approaches. Currently, static DFT is considered the default method of applied quantum chemistry in catalysis. In particular, for over 15 years our group has been successfully applying periodic DFT calculations to study mechanisms of catalytic reactions. Nowadays we are able to analyse highly complex extended reaction networks by applying periodic DFT methods to realistic zeolite models. However, recently it became recognized that standard DFT approaches may fail when, for example, the catalytic reaction may proceed via multiple competitive reaction channels on a highly complex potential energy surface (PES) [Van Speybroeck et al., Chem. Eur. J., 21 (2015) 9385]. Furthermore, for reactions taking place at high temperature, the actual free energy surface (FES) may substantially differ from that constructed from DFT calculations with harmonic approximation [Bell et al., J. Am. Chem. Soc., 134 (2012) 19468]. It has been demonstrated that a correct sampling of conformational space is necessary to adequately describe zeolite-catalyzed processes [Hafner et al., J. Catal., 329 (2015) 32; J. Phys.: Condens. Matter, 22 (2010) 384201]. In addition to the complexity related to the shape of PES, complexity of electronic structure itself is a challenge for DFT. This is particularly true for multinuclear paramagnetic transition metal complexes, which often represent the active component of selective oxidation catalysts. Such system necessitate the use of more advanced multireference ab initio techniques. This proposal therefore aims at applying advanced quantum chemical methodologies to evaluating the effects of complex reaction paths and electronic structures on important catalytic systems.

Kenmerken

Projectnummer

16085

Hoofdaanvrager

Dr. E.A. Pidko

Verbonden aan

Technische Universiteit Eindhoven, Faculteit Scheikundige Technologie, Anorganische Chemie en Katalyse