TY - JOUR

T1 - First-Principles Simulation of Highly Reactive Systems

T2 - Immediacy on a Femtosecond Time Scale

AU - Frank, Irmgard

AU - Siekmann, Dirk

N1 - Funding Information: I. F. wants to thank Dr. Peter Kraus for very valuable discussions and for giving the basic idea for this study. Part of the calculations were performed on the local cluster of the Leibniz University of Hannover at the RRZN.

PY - 2020/5/4

Y1 - 2020/5/4

N2 - Using Car-Parrinello molecular dynamics we study the first reaction steps of the decomposition of a nitrogen-rich molecule and of a mixture of molecular oxygen and molecular hydrogen. Using the simulated-annealing approach we increase the temperature of the systems till they start to react. Both systems have in common that they react violently and that the precise reaction pathways, respectively the single reaction steps under the chosen conditions are largely unknown. While the first system decomposes completely within some hundred femtoseconds, the latter mixture reacts only partially on this timescale due to entropy. Complex reaction chains involving up to ten hydrogen and oxygen molecules allow for a fast reaction, but require a very specific arrangement. To our knowledge such reaction chains of neutral, stable, ground state molecules were not described before. The hope for a decomposition to nitrogen respectively to water is essentially fulfilled, but side products are observed.

AB - Using Car-Parrinello molecular dynamics we study the first reaction steps of the decomposition of a nitrogen-rich molecule and of a mixture of molecular oxygen and molecular hydrogen. Using the simulated-annealing approach we increase the temperature of the systems till they start to react. Both systems have in common that they react violently and that the precise reaction pathways, respectively the single reaction steps under the chosen conditions are largely unknown. While the first system decomposes completely within some hundred femtoseconds, the latter mixture reacts only partially on this timescale due to entropy. Complex reaction chains involving up to ten hydrogen and oxygen molecules allow for a fast reaction, but require a very specific arrangement. To our knowledge such reaction chains of neutral, stable, ground state molecules were not described before. The hope for a decomposition to nitrogen respectively to water is essentially fulfilled, but side products are observed.

KW - Density functional theory

KW - highly reactive systems

KW - molecular dynamics

KW - reaction mechanisms

UR - http://www.scopus.com/inward/record.url?scp=85084501650&partnerID=8YFLogxK

U2 - 10.1002/slct.202000574

DO - 10.1002/slct.202000574

M3 - Article

AN - SCOPUS:85084501650

VL - 5

SP - 5109

EP - 5116

JO - ChemistrySelect

JF - ChemistrySelect

SN - 2365-6549

IS - 17

ER -