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Quadratic transverse anisotropy term due to dislocations in Mn12-Ac directly obtained by EPR spectroscopy

R. Amigo·E. del Barco·Ll. Casas·E. Molins·J. Tejada·I. B. Rutel·B. Mommouton·N. Dalal·J. Brooks
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Abstract

High-Sensitivity Electron Paramagnetic Resonance experiments have been carried out in fresh and stressed Mn12-Acetate single crystals for frequencies ranging from 40 GHz up to 110 GHz. The high number of crystal dislocations formed in the stressing process introduces a E(S_x^2-S_y^2) transverse anisotropy term in the spin hamiltonian. From the behaviour of the resonant absorptions on the applied transverse magnetic field we have obtained an average value for E = 22 mK, corresponding to a concentration of dislocations per unit cell of c = 10^-3.

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R. Amigo, E. del Barco, Ll. Casas, E. Molins, J. Tejada, I. B. Rutel, B. Mommouton, N. Dalal, J. Brooks. 2001-11-12. Quadratic transverse anisotropy term due to dislocations in Mn12-Ac directly obtained by EPR spectroscopy. https://doi.org/10.1103/physrevb.65.172403

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