Many-spin effects and tunneling splittings in Mn 12 magnetic molecules

• Published in: Journal of magnetism and magnetic materials Vol. 246; no. 3; pp. 392 - 398
• Main Authors: De Raedt, H.A., Hams, A.H., Dobrovitski, V.V., Al-Saqer, M., Katsnelson, M.I., Harmon, B.N.
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01-05-2002
• Subjects: Magnetic molecules; Numerical diagonalization; Splittings; Tunneling; 75.10.Dg; 75.40.Mg; 75.45.+j; 75.50.Xx; Tunneling; Splittings; Magnetic molecules; Numerical diagonalization
• ISSN: 0304-8853
• DOI: 10.1016/S0304-8853(02)00111-7

We calculate the tunneling splittings in a Mn
12 magnetic molecule taking into account its internal many-spin structure. We discuss the precision and reliability of these calculations and show that restricting the basis (limiting the number of excitations taken into account) may lead to significant error (orders of magnitude) in the resulting tunneling splittings for the lowest energy levels, so that an intuitive picture of different decoupled energy scales does not hold in this case. Possible routes for further development of the many-spin model of Mn
12 are discussed.