ISSN:
1572-9540
Source:
Springer Online Journal Archives 1860-2000
Topics:
Physics
Notes:
Abstract Quadrupole-interaction nuclear-orientation experiments were performed on dilute samples of the Group IIIb and IVb impurities173Lu and175Hf in a (Group VIIb) Re single crystal, the samples being preparedin situ by irradiation of a Re single crystal with 172.5 MeV alpha particles. From the γ-anisotropies at temperatures down to 8mk the quadrupole interaction frequencies ΝQ=e2qQ/h of173LuRe and175HfRe were determined to be −1149 (100) and −540 (43) MHz, respectively. The negative sign in both cases indicates that the direction of the electric field gradient (EFG) at the impurity sites is fixed uniquely by the properties of the host lattice. The absolute magnitudes of these EFG's differ strongly from that of the pure system ReRe; the electronic contribution to the EFG of different impurities in Re decreases with increasing impurity valence, contrary to the expectation. As a byproduct, the quadrupole splittings of178Ta,182m, 183, 184, 186Re in Re were measured to be −103(10), −502(30), −281(20), −340(22) and −73(7) MHz.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF02159727
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