3d Wavefunctions in 57Fe Mössbauer Spectroscopy

In a remarkable article, Ganiel has shown that 57Fe quadrupole splitting due to a single 3d electron is constant, for any real wavefunction with real coefficients spanning either the T2g or Eg subspaces. We examine here the effects on Vzz and η and show that these vary in complex fashion. Hence, the sensitive effects of structure and bonding on the efg tensor can be buried in a constant quadrupole splitting for this case, and the values of Vzz and η must be extracted by magnetic perturbation or other methods if the nature of the 3d wavefunctions is to be determined.