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The electric field gradient (EFG) parameters were calculated for the binary system Hf2X (X = Al, Si, Ni, Ga and Ge), using the full-potential linear augmented plane wave method, applying the generalized gradient approximation. The major contribution to the EFG value in these compounds comes from the p–p contribution next to the probe nucleus. The only other significant contribution is a d–d contribution to the nickel site in Hf2Ni, arises from the broad spatial distribution of the nickel 3d electrons. The similarity in the electronic properties of the Hf2X compounds, with the exception of Hf2Ni, can be attributed to the resemblance of the crystallographic structure and the alike electronic structure of the X-ligand atom, having one or two p-electrons in the external orbital with close shells below. [ABSTRACT FROM AUTHOR]

The electric field gradient (efg) parameters were calculated for the ternary system Hf XY ( X = Si, Ge; Y = S, Se, Te), using the full-potential linear augmented plane wave (LAPW) method applying the generalized gradient approximation (GGA). The major contribution to the efg value in these compounds comes from the p-p contribution next to the probe nucleus. The intermetallic compounds Hf XY ( X = Si, Ge; Y = S, Se, Te) show similar electronic properties. This similarity can be attributed to the resemblance of the crystallographic structure and the alike electronic structure of the X and Y ligand atoms, having two and four p-electrons in the external orbital, respectively. [ABSTRACT FROM AUTHOR]

Diffusion measurements on lithium atoms adsorbed on a ruthenium single crystal were performed in the high temperature regime (1100–1200 K). Pulsed NMR techniques were utilized to produce and observe the decay of magnetization patterns from which the diffusion coefficient was extracted. The observed temperature dependence could be described by D = (10 ± 7) cm2/s · exp (−(0.46 ± 0.07) eV/kT). The extremely high diffusion coefficient and prefactor are understood by a gas like adsorbate behavior. The electric field gradient has been measured with 7Li: V zz = −5.0 ± 0.1 1015 V/cm2 with an inhomogeneity of less then 1% as judged by the width of the satellite transitions. [ABSTRACT FROM AUTHOR]

The perturbed angular correlation method (PAC) was applied to investigate the lattice location of implanted 111In probe ions in Hf2Ni and Zr2Ni intermetallic compounds. It is concluded that the 111In/111Cd probe nuclei experiencing the highly asymmetric electric field gradient (EFG) occupy the unique hafnium or zirconium 8( h) sites in the investigated phases. Above room temperature, the EFGs decrease linearly with temperature. The results are compared with that of previous PAC measurements with 181Ta probes. [ABSTRACT FROM AUTHOR]