Question

Ferromagnetism and exchange interaction.  Consider dysprosium (Dy), which is a rare earth metal with a density of 8.54 g/cm and atomic mass of 162.50 g/mol.  The isolated atom has the electron structure [Xe]4f¹⁰6s².  

(a) What is the spin magnetic moment in the isolated atom in terms of Bohr magnetons?  

(b) If the saturation magnetization of Dy near absolute zero temperature is 2.4 MA/m, what is the effective number of spins per atom in the ferromagnetic state?  

(c) How does this compare to with the number of spins in the isolated atom?  

(d) What is the order of magnitude for the exchange interaction in eV per atom in Dy if the Curie temperature is 85 K?

Answer 1