title: Calibration of the isomer shift for the 77.34 keV transition in 197Au using the full-potential linearized augmented plane-wave method.
abstract: The isomer shift calibration constant has been calculated for the 77.34 keV Mossbauer transition connecting the ground state of the (197)Au nucleus with the first excited state of this nucleus. The full-potential linearized augmented plane-wave method was used in the fully relativistic approach, albeit without taking into account the spin-orbit coupling. The final assignment of the calibration constant was based on calculations performed for AuCN, AuCl(3), AuBr(3), KAuCl(4), KAuBr(4), and metallic gold. It is found that the calibration constant takes on the following value alpha = +0.0665(4) mm s(-1) a.u.(3). The error quoted is due to the linear regression fit, and the real error might be as large as 10%. The spectroscopic electric quadrupole moment for the ground state of the (197)Au nucleus was calculated as the by-product. It was found that this moment equals Q(g) = +0.566(1)b in fair agreement with the accepted value based on the muonic hyperfine spectroscopy results. The error quoted is again due to the linear regression fit and the real error might be as large as 10%. The final assignment of the value for the quadrupole moment is based on the calculations for the following compounds: AuCl, AuBr, AuI, AuCN, and AuMn(2). Results for the magnetically ordered Au(2)Mn were applied to determine the sign of the quadrupole moment.
authors.affiliation: Applied Computer Science Division, Institute of Technology, Pedagogical University, PL-30-084 Cracow, ul. Podchorazych 2, Poland.
authors.forename: U D
authors.initials: UD
authors.lastname: Wdowik
authors.forename: K
authors.initials: K
authors.lastname: Ruebenbauer