2004/05/04 by Kyungwha Park, Mark R. Pederson · 3 citations
Materials Science · Physics and Astronomy · #Lanthanide and Transition Metal Complexes #Magnetism in coordination complexes #Porphyrin and Phthalocyanine Chemistry #cond-mat.mtrl-sci
paper · pdf · doi:10.1103/physrevb.70.054414
Submitted to Phys. Rev. B
arxiv created 2004/05/04 · openalex publication_date 2004/08/20 · arxiv updated 2009/12/01 · openalex created_date 2016/06/24 · openalex updated_date 2026/07/28
To understand the effect of molecular environment on the electronic and magnetic properties of the single-molecule magnet Mn12, we explore two possible means for adding extra electrons to molecule. We explore both substitution of Mn ions by Fe ions and the inclusion of neighboring electronic donors. For both possibilities we calculate, within density-functional theory, the electronic structure, the total ground-state spin and ordering, the magnetic anisotropy barrier, the transverse magnetic anisotropy parameter E which is responsible for some measured tunneling, and the tilting angle of the easy axis from the z axis. Our calculations show that the total spin increases with increasing number of extra electrons except for the case of Mn8Fe4 where the resulting ground state has a low spin. The calculated energy gaps between the unoccupied and the occupied orbitals exhibit no clear trend as a function of number of extra electrons. The calculated magnetic anisotropy barrier decreases with an increasing number of extra electrons and can be directly traced to a quenching of Jahn-Teller distortions at the sites where the additional electrons are localized. The values of E and the easy-axis tilting angles for the geometries with one- and two-extra electrons are significantly larger than those induced by solvent disorder.