Bonn 2025 – wissenschaftliches Programm
Bereiche | Tage | Auswahl | Suche | Aktualisierungen | Downloads | Hilfe
A: Fachverband Atomphysik
A 40: Cluster and Nanoparticles II (joint session MO/A)
A 40.3: Vortrag
Freitag, 14. März 2025, 11:45–12:00, HS XV
Insights into Facile Methane Activation by Transition Metal Ions via Intersystem Crossing — Marcel Meta, Maximilian Huber, •Maurice Birk, Martin Wedele, Boris Heeb, and Jennifer Meyer — RPTU Kaiserslautern-Landau, Fachbereich Chemie und Landesforschungszentrum OPTIMAS, Kaiserslautern, Germany
A model for processes like single atom catalysis can be the study of isolated transition metal ion molecule reactions in the gas phase [1,2].
Here, we present a study of kinetics and dynamics on the activation of methane (CH4) by transition metal cations M++CH4 → MCH2++H2.
The nominally spin-forbidden reaction requires intersystem crossing (ISC) to proceed.
The impact of ISC on the dynamics is studied by collaborative effort combining experiment and theory.
We used crossed-beam velocity map imaging to measure differential cross sections for the carbene formation in the reaction with tantalum Ta+ [3].
The reaction shows dominantly indirect dynamics which is associated to the formation of a long-lived intermediate complex. Experiments for Ta+ are furthermore complemented by the reaction of CH4 with zirconium Zr+.
In addition recent preliminary theoretical studies confirmed our observations regarding the reaction with Ta+ and also revealed that the bottleneck of this reaction is ISC between the quintet and triplet states.
[1] D. K. Böhme, H. Schwarz, Angew. Chem. Int. Ed. 2005, 44, 2336;
[2] H. Schwarz, Catal. Sci. Tech. 2017, 7, 4302;
[3] M. Meta, Faraday Discuss. 2024, 251, 587
Keywords: Crossed-Beams; Velocity Map Imaging; Methane; Tantalum; Zirconium