An examination of the 140°c phase transition in triammonium hydrogen sulphate (NH4)3H(SO4)2 using synchrotron radiation white-beam topography

The application of synchrotron radiation white-beam topography to characterising the nature and role of lattice defects in solid-state phase transformations is described together with instrumental facilities developed at the Daresbury synchrotron radiation source. The application and limitation of these techniques to an examination of the 140°C phase transition in nearly perfect single crystals of (NH4)3H(SO4)2 is presented and discussed. © 1992, Taylor & Francis Group, LLC. All rights reserved.