Nuclear magnetic resonance of <sup>209</sup>Bi in a BiVO<sub>4</sub> single crystal
A R Lim; S H Choh; M S Jang; A R Lim; Dept. of Phys., Korea Univ., Seoul, South Korea; S H Choh; Dept. of Phys., Korea Univ., Seoul, South Korea; M S Jang; Dept. of Phys., Korea Univ., Seoul, South Korea
Журнал:
Journal of Physics: Condensed Matter
Дата:
1992-02-10
Аннотация:
Nuclear magnetic resonance spectra of <sup>209</sup>Bi(I=9/2) in the ferroelastic BiVO<sub>4</sub> single crystal has been investigated by employing a wide-line Varian spectrometer. Only three lines due to a large quadrupole interaction were measured at a fixed frequency of 6 MHz in the principal planes at room temperature. From the experimental data the quadrupole coupling constant E<sup>2</sup>qQ/h=79.2+or-0.1 MHz and asymmetry parameter eta =0.70+or-0.01 are determined; however, these values turn out to be quite different from the previous report obtained with a ceramic sample at liquid-nitrogen temperature. The principal axes of the electric field gradient tensor are determined for the first time, the x, y and z axes being the crystallographic c+25 degrees , a+25 degrees , and b axes, respectively. Thes directions are discussed in terms of the Bi-O bonds in the Bi-O polyhedra.
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