Lifshitz-point instabilities and re-entrant incommensurability in xH. Katzke1, M. Czank1 and P. Tolédano1, 2
1 Institute of Geosciences, Crystallography, University of Kiel Olshausenstraße 40, 24098 Kiel, Germany
2 Group "Structure of Materials under Extreme Conditions" SNBL/ESRF 38043 Grenoble Cedex, France
(Received 31 March 2003; accepted in final form 21 November 2003)
The concentration-induced sequence of three incommensurate phases ( , , ) previously disclosed in x are interpreted as resulting from distinct Lifshitz-invariant and Lifshitz-points instabilities. When varying the temperature, the phase displays a re-entrant behavior, which is described as a folding of the high-temperature region triggered by the ordering of the lithium ions.
64.60.-i - General studies of phase transitions.
© EDP Sciences 2004