Spin-orbit coupling of sp² nanocarbons and magnetism of fullerene C₆₀ in view of spin peculiarities of unrestricted Hartree–Fock solution

ABSTRACT

The paper presents the first application of unrestricted Hartree–Fock formalism to the consideration of spin-orbit coupling (SOC) of open-shell systems in general and sp² nanocarbons in particular. The SOC parameters determination is exhibited on the example of stretched ethylene. g-Factor determination addresses fullerene C₆₀ due to its peculiar “paradiamagnetic” behavior at low temperature characterized by a set of local spins with different g-factors. The approach application has allowed not only to suggest a reliable explanation of the factor variability but to supplement it by a quantitative agreement with experimental data.

KEYWORDS:

• Magnetism of C₆₀
• Spin-orbit coupling
• Local spins
• Unrestricted Hartree–Fock formalism
• Open shell systems

Acknowledgments

The authors are grateful to V. Sheka, E. Rashba, I. Mayer, J. Karwowski, S. Vinitskii, A. Gusev, and Yu.P. Rybakov for fruitful discussions and S.V. Demishev for kind permission to use experimental data at our discretion. The work was performed under financial support of the Peoples’ Friendship University of Russia, grant: 022203-0-000.