Landau model for the phase diagrams of the orthorhombic rare-earth manganites RMnO3 (R = Eu, Gd, Tb, Dy, Ho)

The present work aims to describe, within a single phenomenological approach, the specific sequence of phase transitions observed in the rare-earth manganites RMnO3 at zero magnetic field. It is shown that a single integrated description of the temperature versus composition phase diagrams of these compounds and related solid solutions can be obtained within the scope of Landau theory by adopting the so-called type-II description of the modulated phases.