Electron interaction with copper(II) carboxylate compounds.

Area of Science:

• Coordination Chemistry
• Physical Chemistry
• Mass Spectrometry

Background:

• Copper carboxylate complexes are important in various chemical applications.
• Understanding their fragmentation patterns under electron impact is crucial for characterizing their stability and reactivity.
• Previous studies have explored the electron-induced reactions of metal complexes, but detailed fragmentation pathways for these specific copper carboxylates are less understood.

Purpose of the Study:

• To investigate the electron collision dynamics of novel copper carboxylate complexes.
• To identify the fragmentation patterns and ion yields of positive and negative ions.
• To elucidate the influence of amine ligands on the dissociation pathways.

Main Methods:

• Utilized crossed electron-molecular beam experiments.
• Employed mass spectrometry to analyze fragmentation patterns.
• Measured the dependence of ion yields on electron energy.

Main Results:

• Observed sequential loss of carboxylate and amine ligands, as well as ligand fragmentation below m/z 140.
• Identified metallated ions confirming the evaporation of whole complex molecules.
• Noted significant Cu+ ion production for [Cu2(µ-O2CC2F5)4] and weak production for [Cu2(EtNH2)2(µ-O2CC2F5)4].
• Dissociative electron attachment (DEA) processes leading to negative ions were similar across complexes, forming Cu2(O2CC2F5)4-• and mononuclear fragments.
• Dominant DEA fragments were formed via single-particle resonant processes near 0 eV.

Conclusions:

• The electron collision experiments provide a detailed understanding of the fragmentation mechanisms of copper carboxylate complexes.
• The presence and type of amine ligands influence the fragmentation pathways, particularly the production of specific copper-containing ions.
• The observed DEA processes highlight the role of the highest unoccupied molecular orbital in negative ion formation.