EPR ofMn2+-doped single crystals of ZnK2(SO4)2·6H2O and NiK2(SO4)2·6H2O:Mn2+-Ni2+exchange constant

Abstract

$X$-band EPR measurements on ${\mathrm{Mn}}^{2+}$-doped single isostructural crystals of diagmagnetic zinc potassium sulfate hexahydrate and paramagnetic nickel potassium sulfate hexahydrate have been made at room, liquid-nitrogren, and liquid-helium temperatures. To avoid the damagnetization effects, a spherical-shaped sample was used for the paramagnetic lattice. The spin-Hamiltonian parameters were evaluated using a least-squares fitting method, simultaneously fitting all resonant line positions obtained for several orientations of the external magnetic field. Using the $g$ shift in the paramagnetic host, from that in the isostructural diamagnetic host, the ${\mathrm{Mn}}^{2+}$-${\mathrm{Ni}}^{2+}$ exchange constant has been estimated.