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Magnetic anisotropy quadrupole broadening

In contrast, soft magnetic solids and paramagnetic systems with weak anisotropy may be completely polarized by an applied field, that is, the effective field at the Mossbauer nucleus is along the direction of the applied field, whereas the EFG is powder-distributed as in the case of crystallites or molecules. In this case, first-order quadrupole shifts cannot be observed in the magnetic Mossbauer spectra because they are symmetrically smeared out around the unperturbed positions of hyperfine fines, as given by the powder average of EQ mj, d, in (4.51). The result is a symmetric broadening of all hyperfine fines (however, distinct asymmetries arise if the first-order condition is violated). [Pg.108]

While MAS and CP-MAS are often sufficient to resolve chemical sites for nuclei like C, P and Si, this is not the case for other nuclei such as ZAl, and B. The reason is that the first group of nuclei have spin while the second have higher spin. Nuclei with spin greater than are subject to electric quadrupole effects, in addition to chemical shift, and these effects present a significant additional source of line-broadening. Because the quadrupole anisotropy in the presence of a strong magnetic field does not transform simply like a 2nd rank tensor, it cannot be... [Pg.964]


See other pages where Magnetic anisotropy quadrupole broadening is mentioned: [Pg.155]    [Pg.155]    [Pg.232]    [Pg.64]    [Pg.10]    [Pg.63]    [Pg.271]    [Pg.272]    [Pg.197]    [Pg.1308]    [Pg.141]    [Pg.3405]    [Pg.3405]    [Pg.102]    [Pg.8]    [Pg.102]    [Pg.112]    [Pg.965]    [Pg.40]    [Pg.274]   
See also in sourсe #XX -- [ Pg.262 , Pg.470 ]




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