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Updated: Jun 27, 2026

A Technical Guide for Performing Spectroscopic Measurements on Metal-Organic Frameworks
Published on: April 28, 2023
Photoelectron spectroscopic study of the anionic transition metalorganic complexes [Fe(1,2)(COT)](-) and [Co(COT)](-)
Xiang Li1, Soren N Eustis, Kit H Bowen
1Department of Chemistry, Johns Hopkins University, Baltimore, Maryland 21218, USA.
Abstract:
The gas-phase, iron and cobalt cyclooctatetraene cluster anions, [Fe(1,2)(COT)](-) and [Co(COT)](-), were generated using a laser vaporization source and studied using mass spectrometry and anion photoelectron spectroscopy. Density functional theory was employed to compute the structures and spin multiplicities of these cluster anions as well as those of their corresponding neutrals. Both experimental and theoretically predicted electron affinities and photodetachment transition energies are in good agreement, authenticating the structures and spin multiplicities predicted by theory. The implied spin magnetic moments of these systems suggest that [Fe(COT)], [Fe(2)(COT)], and [Co(COT)] retain the magnetic moments of the Fe atom, the Fe(2) dimer, and the Co atom, respectively. Thus, the interaction of these transition metal, atomic and dimeric moieties with a COT molecule does not quench their magnetic moments, leading to the possibility that these combinations may be useful in forming novel magnetic materials.
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