Coordination Compounds of Iridium

After a first brief report by Thomson et al. [270] on isomer shifts of the 73 keV 

The compounds containing the hexahalogen complexes [IrCle], [IrBrs] with Ir(lV) formal oxidation state and iridium hexafluoride with hexavalent 

7 Mossbauer-Active Transition Metals Other than Iron 

Each of the eight hyperfine resonances is an unresolved quadmpole doublet, due to the quadmpole interaction of Os in the hexagonal Os metal source. The authors have interpreted the hyperfine fields in terms of core polarization, orbital and spin-dipolar contributions. 

An interesting effect, called hyperfine anomaly, has been observed by Wagner and Zahn [268] and by Perlow et al. [275] for the 73 keV transition of Ir, which apparently has favorable characteristics to establish this phenomenon. 

---