27Al NMR study in ZrNiAl.
We have studied the microscopic properties of the hexagonal ZrNiAl, a model compound for a wide family of intermetallic compounds crystallizing in this type of structure, by using 27Al NMR spectroscopy. We have investigated the lineshape of static and MAS NMR spectra as a function of magnetic field strength (4.7-9.4 T) and temperature (5-300 K). Our data indicate that the 27Al NMR spectra result from a combined effect of quadrupole and anisotropic shift interactions. The 27Al nuclei are in an environment characterized by the quadrupole coupling constant e2qQ/h of 3.3 MHz, asymmetry parameter etaQ of 0.42, isotropic shift delta(iso) of 393 ppm, shift anisotropy delta(anis) = delta(zz) - (delta(xx) + delta(yy))/2 of 150 ppm, and asymmetry factor etaS of 0.5. They are found to be temperature independent. The spin-lattice relaxation rate measured at 7.05 T is proportional to the temperature with T1T = 135 s K. The mechanisms responsible for observed values of delta(iso), delta(anis), T1T, and the enhanced Korringa constant are discussed.
Nowak
B
B
W. Trzebiatowski Institute of Low Temperature and Structure Research, Polish Academy of Sciences, Wrocław. bnowak@int.pan.wroc.pl
Hayashi
S
S
D000535:Aluminum / Q000737:chemistry*; D016880:Anisotropy; D009682:Magnetic Resonance Spectroscopy; D009532:Nickel / Q000737:chemistry*; D011868:Radioisotopes; D013057:Spectrum Analysis; D015040:Zirconium / Q000737:chemistry*
D011868:Radioisotopes; C433593:ZrNiAl; D009532:Nickel; D015040:Zirconium; D000535:Aluminum