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Updated: Mar 28, 2026
Thermochemical Studies of NiII and ZnII Ternary Complexes Using Ion Mobility-Mass Spectrometry
Published on: June 8, 2022
Inter- versus Intramolecular Structural Manipulation of a Dichromium(II) Pacman Complex through Pressure Variation
Charlotte J Stevens1, Alessandro Prescimone1, Floriana Tuna2
1EaStCHEM School of Chemistry, University of Edinburgh , David Brewster Road, Edinburgh EH9 3FJ, U.K.
Abstract:
The effect of pressure on the intranuclear M···M separation and intermolecular secondary interactions in the dinuclear chromium Pacman complex [Cr2(L)](C6H6) was evaluated because this compound contains both a short Cr···Cr separation and an exogenously bound molecule of benzene in the solid state. The electronic structure of [Cr2(L)] was determined by electron paramagnetic resonance spectroscopy, SQUID magnetometry, and density functional theory calculations and shows a diamagnetic ground state through antiferromagnetic exchange, with no evidence for a Cr-Cr bond. Analysis of the solid-state structures of [Cr2(L)](C6H6) at pressures varying from ambient to 3.0 GPa shows little deformation in the Cr···Cr separation, i.e., no Cr-Cr bond formation, but instead a significantly increased interaction between the exogenous arene and the chromium iminopyrrolide environment. It is therefore apparent from this analysis that [Cr2(L)] would be best exploited as a rigid chemical synthon, with pressure regulation being used to mediate the approach and secondary interactions of possible substrates.
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