کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
9834171 1524907 2005 4 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Exchange constants and spin dynamics in Mn12-acetate
موضوعات مرتبط
مهندسی و علوم پایه فیزیک و نجوم فیزیک ماده چگال
پیش نمایش صفحه اول مقاله
Exchange constants and spin dynamics in Mn12-acetate
چکیده انگلیسی
We have obtained new inelastic neutron scattering (INS) data for the molecular magnet Mn12-acetate which exhibit at least six magnetic peaks in the energy range 5-35 meV. These are compared with a microscopic Heisenberg model for the 12 quantum spins localised on the Mn ions, coupled by four inequivalent magnetic exchange constants. A fit to the magnetic susceptibility under the constraint that the spin of the ground state be S=10 yields two dominant exchange constants of very similar value, J1≈J2≈65 K (≈5.5 meV), and two smaller exchange constants J3 and J4. We compute the low-lying excitations by exact numerical diagonalisation and demonstrate that the parameters determined from the ground state and susceptibility fit provide qualitative agreement with the excitations observed by INS.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Journal of Magnetism and Magnetic Materials - Volumes 290–291, Part 2, April 2005, Pages 966-969
نویسندگان
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