Title :
Transformation-induced evolution of far-infrared vibrational modes in theophylline
Author :
Upadhya, P.C. ; Nguyen, K.L. ; Shen, Y.C. ; Obradovic, J. ; Fukushige, K. ; Griffiths, R. ; Gladden, L.F. ; Davies, A.G. ; Linfield, E.H.
Author_Institution :
Cavendish Lab., Cambridge Univ., UK
fDate :
27 Sept.-1 Oct. 2004
Abstract :
Time-resolved terahertz (THz) spectroscopy has been used to characterize polymorphic transformations in crystalline theophylline, a widely used pharmaceutical compound. On transformation, different inter-molecular bonding arrangements arise, leading to distinct THz spectral signals. Changes between polymorphic forms were confirmed by IR and powder X-ray diffraction measurements.
Keywords :
X-ray diffraction; infrared spectra; organic compounds; pharmaceuticals; polymorphic transformations; submillimetre wave spectra; time resolved spectra; vibrational modes; IR measurements; THz spectral signals; crystalline theophylline; intermolecular bonding; pharmaceutical compound; polymorphic transformations; powder X-ray diffraction measurements; time resolved THz spectroscopy; time resolved terahertz spectroscopy; transformation induced far-infrared vibrational modes; Bonding; Crystallization; Electromagnetic wave absorption; Infrared spectra; Mirrors; Powders; Raman scattering; Solids; Spectroscopy; X-ray diffraction;
Conference_Titel :
Infrared and Millimeter Waves, 2004 and 12th International Conference on Terahertz Electronics, 2004. Conference Digest of the 2004 Joint 29th International Conference on
Print_ISBN :
0-7803-8490-3
DOI :
10.1109/ICIMW.2004.1422145
