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Updated: Mar 30, 2026

Exploring the Radical Nature of a Carbon Surface by Electron Paramagnetic Resonance and a Calibrated Gas Flow
Published on: April 24, 2014
Conformational Effects on the Magnetic Properties of an Organic Diradical: A Computational Study
Vincenzo Barone1, Corentin Boilleau1, Ivo Cacelli2
1Scuola Normale Superiore, Piazza dei Cavalieri, I-56126 Pisa, Italy.
Abstract:
A theoretical study on the singlet triplet energy splitting in a m-phenylene bridged organic diradical has been performed using an original computational protocol developed in our group. The method is based on post Hatree-Fock calculations and has proven to provide accurate results with reasonable computational effort. By virtue of such efficiency, the full PES of both the singlet and triplet states as a function of the two "soft" torsional degrees of freedom at the meta position of the ring has been explored. In agreement with literature findings, we found a pronounced dependence of the sign of the energy gap from the torsional angles. Finally, exploiting the two-dimensional surface, a statistical analysis is carried out at low temperatures and a comparison with available experimental data addressed.
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