Phonon dynamics of hexagonal Y Mn1−xFexO3

Phonon dynamics was investigated on Y Mn1−xFexO3(0≤x≤0.200≤x≤0.20) hexagonal manganite polycrystals. Phonon modes were properly assigned using results obtained on Y MnO3 single crystal, by mixing the abab plane and the cc axis optical responses. Upon increasing the Fe content, most of the phonon mode frequencies do not vary drastically. However, some modes involving Y and O atom displacements along the cc axis are affected by doping. Indeed, a redshift of their transverse optical frequency was interpreted as an elongation of Y–O distance along the cc-axis, resulting in a change in yttrium coordination.

► Optical study of Y Mn1−xFexO3.
► Phonon mode assignment and anomalous Fe dependence.
► Y coordination change with Fe doping.