Quantum chemical approaches to [NiFe] hydrogenase

Abstract

The mechanism by which [NiFe] hydrogenase catalyzes the oxidation of molecular hydrogen is a significant yet challenging topic in bioinorganic chemistry. With far-reaching applications in renewable energy and carbon mitigation, significant effort has been invested in the study of these complexes. In particular, computational approaches offer a unique perspective on how this enzyme functions at an electronic and atomistic level. In this article, we discuss state-of-the art quantum chemical methods and how they have helped deepen our comprehension of [NiFe] hydrogenase. We outline the key strategies that can be used to compute the (i) geometry, (ii) electronic structure, (iii) thermodynamics and (iv) kinetics properties associated with the enzymatic activity of [NiFe] hydrogenase and other bioinorganic complexes.

Computational optimization of electric fields for better catalysis design

“…62,63 This line of research has allowed for accurate rate constant prediction for molecule-surface reactions 64 , while Piccini et al showed how energy barriers for large systems like zeolites (over 1000 atoms) could be calculated within chemical accuracy (within 4 kJ/mol) using Density Functional Theory (DFT) methods. 65 But there are still significant difficulties for metal catalysts, for example metalloenzymes, where there may be multiple reactive sites requiring a QM description 66 , and for which errors in relative free energies do not generally fall below 20 kJ/mol due to poor accounting of strong correlation using DFT 67 .…”

Molecular Electrocatalysts for the Hydrogen Evolution Reaction: Input from Quantum Chemistry

“…These enzymes, knowna sh ydrogenases, have catalytic efficiency that is unmatched by any manmadec atalyst. [6] 3. Unfortunately,d ue to their intricate architecture, there has not been ap recise agreement on how hydrogenases function.…”

“…[4, 5b] For am ore in-depth analysis on theoretical methods involved in these studies, we refer the readert oa ne xcellent review by Vaissier and VanV oorhis. [6]…”

“…This quest has been inspiredb yh ydrogenases,w hich are organometallice nzymes that employn ickel and/ori ron centers in their active sites. [6] Due to the aforementioned difficulties, avast number of articles have been published on biomimetic [7] or bioinspired [8] systems;t hese consist of either simpler or adapted versionso f the metal centers found in the active sites of hydrogenases ( Figure 1). With turnover rates of up to 10 4 s À1 ,t hermostability, and lowo verpotentials, [4] hydrogenases have been studied as templates for the synthesis of new organometallic catalysts.…”

“…[5] Moreover,f rom at heoretical point of view,t he size and composition of their active sites make them challenging to study. [6] Due to the aforementioned difficulties, avast number of articles have been published on biomimetic [7] or bioinspired [8] systems;t hese consist of either simpler or adapted versionso f the metal centers found in the active sites of hydrogenases ( Figure 1). The idea is to facilitate the analysis of the hydrogen evolution reaction( HER) in the metal centers, looking for the essential elements that could be used to develop new catalysts…”