Dresden 2011 – wissenschaftliches Programm
Bereiche | Tage | Auswahl | Suche | Aktualisierungen | Downloads | Hilfe
TT: Fachverband Tiefe Temperaturen
TT 3: CE: Charge Density Wave \& Peierls Instability
TT 3.2: Vortrag
Montag, 14. März 2011, 10:45–11:00, HSZ 304
A band structure study of BaNi2P4 - Dimorphism from a Peierls instability? — •Eugen Wolf, Andreas Leithe-Jasper, Christoph Geibel, and Helge Rosner — Max Planck Institute for Chemical Physics of Solids, 01187 Dresden, Germany
The recent discovery of high temperature superconductivity in iron pnictide compounds stimulated a rebirth of interest in transition metal pnictides in general. In particular, a focus of attention is devoted to compounds that exhibit structural phase transitions caused by the interplay of electronic and lattice degrees of freedom. Here, we present a density functional based (LDA and GGA) computational study of the compound BaNi2P4 that shows a tetragonal to orthorhombic phase transition at about 370 K. In our calculations, we can reproduce the orthorhombic ground state which is non magnetic since the electronic density of states at the Fermi level is rather low in both phases with a sizably reduced value for the orthorhombic structure. However, the calculated energy difference between the tetragonal and the orthorhombic lattice is far to small to account for the high transition temperature. Possible scenarios for the transition are discussed, especially in the light of a Peierls instability that has been debated controversially in the literature [1,2].
Keimes V, Johrendt D, Mewis A, ZAAC 621, 925, (1995).
Palacios AA, Alemany P, Alvarez S, et al. Annales de quimica - international edition 93, 385-393, (1997).