First-principles modelling of magnetic excitations in Mn12

Abstract

We have developed a fully microscopic theory of magnetic properties of the prototype molecular magnet Mn12. First, the intra-molecular magnetic properties have been studied by means of first-principles density functional-based methods, with local correlation effects being taken into account within the local density approximation plus U (LDA+U) approach. Using the magnetic force theorem, we have calculated the interatomic isotropic and anisotropic exchange interactions and full tensors of single-ion anisotropy for each Mn ion. Dzyaloshinskii-Moriya (DM) interaction parameters turned out to be unusually large, reflecting a low symmetry of magnetic pairs in molecules, in comparison with bulk crystals. Based on these results we predict a distortion of ferrimagnetic ordering due to DM interactions. Further, we use an exact diagonalization approach allowing to work with as large Hilbert space dimension as 10^8 without any particular symmetry (the case of the constructed magnetic model). Based on the computational results for the excitation spectrum, we propose a distinct interpretation of the experimental inelastic neutron scattering spectra.

arXiv comment8 pages, 2 figures. To appear in Physical Review B

References in corpus (10)

• High frequency EPR spectra of a molecular nanomagnet provide a key to understand Quantum Tunneling of the Magnetization
• Weak ferromagnetism in antiferromagnets: Fe${}_2$O${}_3$ and La${}_2$CuO${}_4$
• Effect of local Coulomb interactions on the electronic structure and exchange interactions in Mn12 magnetic molecules
• Magnetic structure of hexagonal YMnO3 and LuMnO3 from a microscopic point of view
• Many-Spin Interactions and Spin Excitations in Mn12
• Electronic Structure and Exchange Interactions of Na${}_2$V${}_3$O${}_7$
• Weak ferromagnetism in Mn nanochains on the CuN surface
• Weak antiferromagnetic ordering and pure magnetic reflections induced by Dzyaloshinskii-Moriya interaction in MnSi-type crystals
• Semiconductive and Photoconductive Properties of the Single Molecule Magnets Mn${}_{12}$-Acetate and Fe${}_8$Br${}_8$
• Many-spin effects and tunneling splittings in Mn12 magnetic molecules

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