2001/06/30 by Kyungwha Park, M. A. Novotny, Naresh S. Dalal +5 · 9 citations
Biochemistry, Genetics and Molecular Biology · Materials Science · Physics and Astronomy · #Electron Spin Resonance Studies #Lanthanide and Transition Metal Complexes #Magnetism in coordination complexes #cond-mat
paper · pdf · doi:10.1103/physrevb.65.014426
published as PRB 65,014426 (2002) · revised version
openalex publication_date 2001/12/11 · arxiv created 2003/02/24 · arxiv updated 2009/11/30 · openalex created_date 2016/06/24 · openalex updated_date 2026/07/28
Electron paramagnetic resonance measurements on single crystals of the molecular magnets Fe8 and Mn12 reveal complex nonlinearities in the linewidths as functions of energy eigenstate, frequency, and temperature. Using a density-matrix equation with distributions of the uniaxial anisotropy parameter D, the Land'e g factor, and dipolar interactions, we obtain linewidths in good agreement with experiments. Our study shows that the distribution in D is common to the examined molecular magnets Fe8 and Mn12 regardless of the qualities of the samples. This could provide the basis for a proposed tunneling mechanism due to lattice defects. The distribution in g is also quite significant for Mn12.