ChemInform Abstract: Pressure and Temperature Dependence of the Eu Valence in EuNi2Ge2 and Related Systems Studied by Moessbauer Effect, X-Ray Absorption, and X- Ray Diffraction.

✍ Scribed by H.-J. HESSE; R. LUEBBERS; M. WINZENICK; H. W. NEULING; G. WORTMANN

• Publisher: John Wiley and Sons
• Year: 2010
• Weight: 28 KB
• Volume: 28
• Category: Article
• ISSN: 0931-7597
• DOI: 10.1002/chin.199724017

✦ Synopsis

X-ray spectra (solids and liquids) D 6510

24 -017

Pressure and Temperature Dependence of the Eu Valence in EuNi2Ge2 and Related Systems Studied by Moessbauer Effect, X-Ray Absorption, and X-Ray Diffraction.

-Pressure-and temp.-induced valence transition of Eu in the ThCr2Si2-type EuNi2Ge2 and related EuNi2Si2, EuNi2Si0.5Ge1.5, and EuPt2Ge2 systems is studied by 151Eu Moessbauer spectroscopy, XRD, and Eu-LIII X-ray absorption. Transitions from a di-towards a trivalent state are observed in EuNi2Ge2 and the quasi-ternary EuNi2Si0.5Ge1.5 system at about 5 and 0.5 GPa, respectively. A new type of valence transition from an initially almost divalent state to two different states is detected in EuNi2Ge2 by Moessbauer spectroscopy at various pressures and temperatures. Both the Eu valence and the magnetic behavior are pressure and temp. dependent.