Chemical shift, chemical shift anisotropy, and spin-lattice relaxation time in Y-89-MAS and -static NMR of yttrium compounds

The chemical shift, the range of chemical shift anisotropy, and the spin-lattice relaxation times (T-1) in Y2O3, Y3Al5O12, and Y2O2S have been measured by solid state Y-89 (nuclear spin 1/2)-MAS and -static NMR. The static NMR data and T-1 are reported for the first time. The range of chemical shift anisotropy was 1500-2400 Hz. This range was influenced more by the nature of the atom bound to Y than by the coordination number or the crystallographic symmetry of Y. Very long T-1 values were obtained for Y2O2S (6.61 h) and Y2O3 (3.92 h at 24d site and 3.81 h at 8b site). On the other hand, the T-1 value (1.10 h) of Y3Al5O12 is much shorter compared with those of Y2O2S and Y2O3. The next-nearest neighboring atom of Y in Y3Al5O12 is identified as Al, which has the nuclear spin 5/2 of 100% natural abundance. The most likely origin of significantly shorter T-1 of Y3Al5O12 is a dipole-dipole interaction between Y-89 and Al-27.