Al-27 nuclear magnetic resonance studies of the Y3-xLuxAl5O12 mixed garnets

The character of the substitutional order, the chemical shift, and the nucl ear quadrupole coupling in the mixed yttrium-lutetium aluminium garnets Y3- xLuxAl5O12 (0 less than or equal to x less than or equal to 3) were studied for the first time using Al-27 magic C, angle spinning (MAS) and multiple quantum (MQ) MAS nuclear magnetic resonance (NMR). The relatively narrow di stribution of the isotropic NMR line shifts, revealed by MQ MAS NMR, in cry stals with compositions x = 0.75 and x = 1 compared to mixed garnets of oth er compositions showed that these crystals are partially ordered solid solu tions. The aluminium quadrupole coupling constants and isotropic chemical s hifts were evaluated for all garnets under study.