Cerium chalcogenides

Svane A, Temmerman W and Szotek Z 1999 Theory of pressure-induced phase transitions in cerium chalcogenides Phys. Rev. B 59 7888... 

TABLE 4 Calculated transition pressures for the electronic and structural phase transitions in the Ce pnictides and chalcogenides. Also quoted are the volume discontinuities (relatively to the zero pressure equilibrium volume) at the transition. The notation (f") refers to SIC-LSD calculations with n localized f-electrons. For the cerium pnictides, B2 denotes the distorted B2 structure. Experimentally, the transitions of the Ce pnictides are discontinuous, while those of the cerium chalcogenides (at room temperature) are continuous... 

CeTe. The B1 B2 transition in cerium chalcogenides has also been investigated within the GGA approach (Bouhemadou et al., 2005), in which case, the f electrons are treated as itinerant. 

The experimental papers cover the various spectroscopic techniques and a few deal with special materials. The introductory chapter (62) by Baer and Schneider presents an overview of this field and helps tie the various aspects together that are reviewed in detail in the remaining chapters of the volume. Photoemission studies (UPS - ultraviolet photoemission spectroscopy, and XPS - X-ray photoemission spectroscopy) on various materials are discussed by Campagna and Hillebrecht (chapter 63)- intermetallic compounds, by Lynch and Weaver (chapter 66)— cerium and its compounds, and by Hiifner (chapter 67) - chalcogenides. Other experimental techniques covered include BIS (bremsstrahlung isochromat spectroscopy) by Hillebrecht and Campagna (chapter 70), X-ray absorption and X-ray emission by Rohler (chapter 71) and inelastic electron scattering by Netzer and Matthew (chapter 72). 

The sum of the two contributions is a skew parabola with its minimum moved towards the beginning of the series. Further, the skewness and the distance of the minimum from the centre of the series increase as the strength of f-p hybridization increases, as shown in fig, 59. A model similar to that summarized in fig. 58 may also be used for actinide transition metal compounds, with d bands replacing the p bands of the chalcogenide or pnictide. The resulting state densities are then similar to those in fig. 40, modified to include f states in the bands, as in sect. 5.3 for cerium compounds. 

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