Transport properties of quasi-two-dimensional Mo4O11 crystals

The electrical resistivity under hydrostatic pressure up to 1.0 GPa, Hall effect, magnetoresistance, and thermoelectric power are measured over the temperature range from 1.5 to 300 K for both, orthorhombic γ-Mo4O11 and monoclinic η-Mo4O11 crystals with quasi-two-dimensional structures. All these properties show anomalies associated with the charge density wave (CDW) transition; particularly the hydrostatic pressure enhances the CDW instabilities through the increased electron-phonon interaction and partial nesting of the Fermi surfaces. It is also found that both, electrons and holes contribute to the conduction processes, for which a qualitative discussion is made. (author)