209Bi NQR Powder Spectra Influenced by Local and Applied Magnetic Fields

Abstract

Abstract Several experimental techniques have shown evidence for the existence of internal magnetic fields of the order of 200 G in α-Bi2O3 [1]. The asymmetrical 209Bi NQR lineshapes in Bi3O4Br also point to a source of poorly resolved splitting present in this compound. In order to obtain further insight into the origin of the local magnetic fields in these compounds the 209Bi NQR lineshapes of polycrystalline a-Bi2O3 and Bi3O4Br were recorded in weak (below 500 G) static magnetic fields. A calculation of the expected powder lineshapes in a-Bi2O3 under the influence of the internal and applied magnetic fields up to 1 kG was made. The results of the computer simulation are compared with the lineshapes recorded. From the 209Bi lineshapes ob­ served in the experiment, the local magnetic field at one of the two Bi-sites in Bi3O4Br was estimated.