K. Ruebenbauer, B. Miczko, T. Birchall
Dec 1, 1989
Physica B-condensed Matter
Abstract A density matrix formalism has been introduced to describe the perturbation of the Mossbauer line intensities caused by the anisotropic recoilless fraction in random absorbers. General properties of the matrix elements are discussed and relationships between thermal tensors and density matrices are investigated with the attention focused on the possibility to extract as much information about the thermal tensors as possible from the observed line intensities. It is shown, that quartic (anharmonic) anisotropy may be observable in quadrupolarly dominated transitions under favourable conditions.