Abstract
Mössbauer spectra for thick gold absorbers have been measured as a function of absorber temperature in the range °K. By fitting these spectra with an appropriate theoretical line-shape function, values of have been obtained, where is the recoilless fraction for metallic gold and is the internal-conversion coefficient for the 77.3- keV state in . The precision in these values is about 1%, except at the higher absorber temperatures. Because of its importance in the thick-absorber line-shape analysis, the natural linewidth for the 77.3-keV state has been redetermined to be 0.923 ± 0.006 mm/sec. Values of for metallic gold have been obtained by reducing our thick-absorber data with . This value of is based on two independent estimates which show good agreement. One estimate uses conversion-intensity data and theoretical internal-conversion coefficients, while the other estimate uses our data and predictions of from a recent quasiharmonic analysis of gold thermodynamic data. The recoilless fraction for metallic gold as determined in our treatment is found to vary from to . Effective Debye temperatures are determined from these recoilless fractions for gold and are compared with corresponding effective Debye temperatures determined from specific-heat measurements.
- Received 4 December 1970
DOI:https://doi.org/10.1103/PhysRevB.3.2180
©1971 American Physical Society