Ordering behaviour of the mineral lawsonite

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 90K ≤T ≤ 633K. Two successive phase transitions have been found at low temperatures. The analysis of t...

Full description

Saved in:
Bibliographic Details
Published inPhase transitions Vol. 71; no. 3; pp. 189 - 203
Main Authors Sondergeld, P., Schranz, W., Kityk, A. V., Carpenter, M. A., Libowitzky, E.
Format Journal Article
LanguageEnglish
Published Reading Taylor & Francis Group 01.01.2000
Taylor and Francis
Subjects
Earth sciences
Earth, ocean, space
Exact sciences and technology
Lawsonite
Mineralogy
Ordering
Phase transitions
Silicates
Young's modulus
sorosilicates
crystal chemistry
unit cell
birefringence
temperature
silicates
lawsonite
phase transitions
dielectric constant
order-disorder
Online AccessGet full text

Cover

More Information
Summary: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 90K ≤T ≤ 633K. 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 (T 1 ) is tricritical. The other transition around 120K. (T 2 ) is of second order and proper ferroelectric. The mineral shows remarkable pretransitional effects in a temperature range up to 200 K. above T 1 . The data below T 2 are interpreted in terms of a mutual interference of the two different ordering processes associated with T 1 and T 2 , respectively.
Bibliography:ObjectType-Article-2
SourceType-Scholarly Journals-1
ObjectType-Feature-1
content type line 23
ISSN:0141-1594
1029-0338
DOI:10.1080/01411590008229651