Shinbyoung Ahn, K. Harris, B. Kariuki
2001
Citations
0
Influential Citations
10
Citations
Journal
IEEE Journal of Solid-state Circuits
Abstract
3-Bromo- trans -cinnamic acid (3-BrCA) exists as two crystalline polymorphic forms (designated as β and γ phases). A polymorphic phase transformation from the γ phase to the β phase has been investigated using ex situ powder X-ray diffraction, in situ high-temperature optical microscopy, and differential scanning calorimetry. The transformation occurs at an observable rate at temperatures above about 100°C. A reverse transformation on subsequently cooling the β phase is not observed. Thermodynamic aspects of the polymorphic 3-BrCA system are discussed, together with kinetic aspects of the transformation from the γ phase to the β phase. The structural properties of the β phase (reported previously) and the γ phase (determined in this work from single-crystal X-ray diffraction data) are in accord with the α / β / γ structural classification of trans -cinnamic acid derivatives.