Ab Initio Molecular Dynamics Study of Water Oxidation Reaction Pathways in Mono-Ru Catalysts

SN2-type halide substitution and hydrolysis are two of the most ubiquitous reactions in chemistry. The interplay between these processes is fundamental in atmospheric chemistry through reactions of N2O5 and seawater. N2O5 plays a major role in regulating levels of O3, OH, NOx, and CH4. While the reactions of N2O5 and seawater are of central importance, little is known about their mechanisms. Of interest is the activation of Cl in seawater by the formation of gaseous ClNO2, which occurs despite the fact that hydrolysis (to HNO3) is energetically more favorable. We determine key features of the reaction landscape that account for this behavior in a theoretical study of the cluster N2O5/Cl−/H2O. This was carried out using ab initio molecular dynamics to determine reaction pathways, structures, and time scales. While hydrolysis of N2O5 occurs in the absence of Cl−, results here reveal that a low-lying pathway featuring halide substitution intermediates enhances hydrolysis.

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Diffusion and reaction pathways of water near fully hydrated TiO2 surfaces from ab initio molecular dynamics

The Journal of Chemical Physics ◽

10.1063/1.4991381 ◽

2017 ◽

Vol 147 (2) ◽

pp. 024704 ◽

Cited By ~ 24

Author(s):

Lorenzo Agosta ◽

Erik G. Brandt ◽

Alexander P. Lyubartsev

Keyword(s):

Molecular Dynamics ◽

Ab Initio ◽

Reaction Pathways ◽

Ab Initio Molecular Dynamics

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Protonation states in a cobalt-oxide catalyst for water oxidation: fine comparison of ab initio molecular dynamics and X-ray absorption spectroscopy results

Physical Chemistry Chemical Physics ◽

10.1039/c1cp21776c ◽

2011 ◽

Vol 13 (34) ◽

pp. 15437 ◽

Cited By ~ 32

Author(s):

Giuseppe Mattioli ◽

Marcel Risch ◽

Aldo Amore Bonapasta ◽

Holger Dau ◽

Leonardo Guidoni

Keyword(s):

Molecular Dynamics ◽

Ab Initio ◽

Cobalt Oxide ◽

Absorption Spectroscopy ◽

Water Oxidation ◽

Oxide Catalyst ◽

Ab Initio Molecular Dynamics ◽

X Ray ◽

X Ray Absorption

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Determination of pKa Values via ab initio Molecular Dynamics and its Application to Transition Metal-Based Water Oxidation Catalysts

Inorganics ◽

10.3390/inorganics7060073 ◽

2019 ◽

Vol 7 (6) ◽

pp. 73 ◽

Cited By ~ 5

Author(s):

Mauro Schilling ◽

Sandra Luber

Keyword(s):

Molecular Dynamics ◽

Reaction Mechanism ◽

Transition Metal ◽

Ab Initio ◽

Water Oxidation ◽

Ab Initio Molecular Dynamics ◽

Oxidation Catalysts ◽

Dynamics Simulations ◽

Further Development

The p K a values are important for the in-depth elucidation of catalytic processes, the computational determination of which has been challenging. The first simulation protocols employing ab initio molecular dynamics simulations to calculate p K a values appeared almost two decades ago. Since then several slightly different methods have been proposed. We compare the performance of various evaluation methods in order to determine the most reliable protocol when it comes to simulate p K a values of transition metal-based complexes, such as the here investigated Ru-based water oxidation catalysts. The latter are of high interest for sustainable solar-light driven water splitting, and understanding of the underlying reaction mechanism is crucial for their further development.

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Structure of phosphorus-selenium glasses: results from ab initio molecular dynamics simulations

Molecular Physics ◽

10.1080/002689700162045 ◽

2000 ◽

Vol 98 (11) ◽

pp. 701-707

Author(s):

Alessandro Sergi, Mauro Ferrario, Francesco Bu

Keyword(s):

Molecular Dynamics ◽

Ab Initio ◽

Molecular Dynamics Simulations ◽

Ab Initio Molecular Dynamics ◽

Dynamics Simulations

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Combustion Driven by Fragment-based Ab Initio Molecular Dynamics Simulation

10.26434/chemrxiv.11462160.v1 ◽

2019 ◽

Author(s):

Liqun Cao ◽

Jinzhe Zeng ◽

Mingyuan Xu ◽

Chih-Hao Chin ◽

Tong Zhu ◽

...

Keyword(s):

Molecular Dynamics ◽

Ab Initio ◽

Large Scale ◽

Methane Combustion ◽

Combustion Method ◽

Dynamics Simulation ◽

Ab Initio Molecular Dynamics ◽

Computational Time ◽

Combustion Mechanism ◽

Daily Lives

Combustion is a kind of important reaction that affects people's daily lives and the development of aerospace. Exploring the reaction mechanism contributes to the understanding of combustion and the more efficient use of fuels. Ab initio quantum mechanical (QM) calculation is precise but limited by its computational time for large-scale systems. In order to carry out reactive molecular dynamics (MD) simulation for combustion accurately and quickly, we develop the MFCC-combustion method in this study, which calculates the interaction between atoms using QM method at the level of MN15/6-31G(d). Each molecule in systems is treated as a fragment, and when the distance between any two atoms in different molecules is greater than 3.5 Å, a new fragment involved two molecules is produced in order to consider the two-body interaction. The deviations of MFCC-combustion from full system calculations are within a few kcal/mol, and the result clearly shows that the calculated energies of the different systems using MFCC-combustion are close to converging after the distance thresholds are larger than 3.5 Å for the two-body QM interactions. The methane combustion was studied with the MFCC-combustion method to explore the combustion mechanism of the methane-oxygen system.

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