Ordering behaviour of the mineral lawsonite
- Author(s)
- Peter Sondergeld, Wilfried Schranz, Andri V Kityk, Michael Allan Carpenter, Eugen Libowitzky
- Abstract
Lawsonite crystals have been investigated by dilatometry and dynamic mechanical analysis as well as by measurements of the optical birefringence and the dielectric constant in the temperature range 90 K = T = 633 K. Two successive phase transitions have been found at low temperatures. The analysis of the spontaneous strain and the excess birefringence data reveals that the transition around 273 K (T1) is tricritical. The other transition around 120 K (T2) is of second order and proper ferroelectric. The mineral shows remarkable pretransitional effects in a temperature range up to 200 K above T1. The data below T2 are interpreted in terms of a mutual interference of the two different ordering processes associated with T1 and T2, respectively.
- Organisation(s)
- Department of Mineralogy and Crystallography
- External organisation(s)
- University of Cambridge, Czestochowa University of Technology (CUT)
- Journal
- Phase Transitions: a multinational journal
- Volume
- 71
- Pages
- 189-203
- No. of pages
- 15
- ISSN
- 0141-1594
- DOI
- https://doi.org/10.1080/01411590008229651
- Publication date
- 2000
- Peer reviewed
- Yes
- Austrian Fields of Science 2012
- 1030 Physics, Astronomy
- Portal url
- https://ucrisportal.univie.ac.at/en/publications/5375e1fb-747f-43f7-9efc-fd19fadcacdd