Time-resolved terahertz spectroscopy: Polymorphic solid state phase transitions in carbamazepine

Author

Zeitler, J.A. ; Taday, P.F. ; Gordon, Keith C. ; Pepper, Michael ; Rades, Thomas

Author_Institution

Univ. of Otago, Dunedin

fYear

2007

fDate

2-9 Sept. 2007

Firstpage

492

Lastpage

493

Abstract

The polymorphic modifications of carbamazepine show distinct spectral features in the far infrared between 2 and 130 cm^-1. Using time-resolved terahertz pulsed spectroscopy the enantiotropic solid state phase transition between two polymorphic forms was recorded. The terahertz spectra revealed that the solid state conversion follows a two step mechanism: form III sublimates and then condenses in a second step as form I. The sublimation and condensation steps follow different kinetics.

Keywords

polymorphic transformations; submillimetre wave spectroscopy; carbamazepine; enantiotropic solid state phase transition; far infrared; polymorphic forms; polymorphic solid state phase transitions; solid state conversion; spectral features; terahertz spectra; time-resolved terahertz pulsed spectroscopy; time-resolved terahertz spectroscopy; Drugs; Heating; Isothermal processes; Kinetic theory; Pharmaceuticals; Solid state circuits; Spectroscopy; Stability; Temperature; Time domain analysis;

fLanguage

English

Publisher

ieee

Conference_Titel

Infrared and Millimeter Waves, 2007 and the 2007 15th International Conference on Terahertz Electronics. IRMMW-THz. Joint 32nd International Conference on

Conference_Location

Cardiff

Print_ISBN

978-1-4244-1438-3

Type

conf

DOI

10.1109/ICIMW.2007.4516597

Filename

4516597