| Summary: | ESR measurements are reported on the transition metal ions Mn²⁺
and Cu²⁺ diffused into sites in, and adjacent to, the conduction
planes of sodium β"-alumina single crystals. The spin-
Hamiltonian parameters obtained for Mn²⁺ are g[sub === ] = 2.0000(2),
G[sub ┴] = 2.0019(2), A [sub === ] = -8.39(3) mT, A[sub ┴] = -8.33 mT and D = -
7.20(5) mT. The Mn²⁺ ions occupy the Al(3) sites adjacent to the
conduction planes. The symmetry of the Cu²⁺ spectra place the
Cu²⁺ ions at the mid-oxygen sites of the conduction planes. The
complex spectra are a superposition of several different
configurations of ions around this site which change as a
function of the amount of Cu²⁺ diffused. The angular variations
of the spectra can be divided into two main types: an
anisotropic site symmetry with spin-Hamiltonian parameters
g[sub === ] =11- 2.355, g[sub a ┴] , 2.087, A [sub === ] = 12.0 mT, A[sub a┴] 2.0 - 4.0 mT, and a more isotropic site symmetry with g [sub i === ] = 2.003, g[sub i┴] = 2.240,
A[sub i === ] = 9.9 mT, A[sub i ┴] = 8.8 mT. These spectra are visible at liquid-
helium temperatures. In addition an anisotropic, random-type spectrum is observed to replace the Cu²⁺ spectra as the temperature of annealed crystals is increased. This is attributed to the thermal motion of the Cu²⁺ ions due to their weak binding to the site. Suitable doping and annealing procedures to diffuse Mn²⁺ and Cu²⁺ into sodium β"-alumina are discussed and contrasted with the markedly different procedures in the case of the β structure. === Science, Faculty of === Physics and Astronomy, Department of === Graduate
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