DAN, 4-(N,N-dimethylamino)-3-acetamidonitrobenzene is an organic nonlinear optical material with particularly high polarizability of the molecule. In order to provide a sound base for the optimization of (flight) crystal growth experiments, we have performed vapor pressure measurements with DAN, and studied the growth morphology at various temperatures. Vapor pressure data were obtained between 50 and 140 degrees C, employing a specially designed, non- contaminating, and computer-controlled experimental set-up. Thermal decomposition of DAN was found to set in around 90 degrees C. Crystal growth morphologies were monitored by optical microscopy at various temperatures. Smoothly faceted growth, indicating adequate surface mobility of adatoms, was obtained at temperatures above 115 degrees C. As a consequence, for crystal growth at this high temperature, continuous removal of decomposition products is required to sustain practical growth rates.

Date Published: 12 July 1996
PDF: 6 pages
Proc. SPIE 2809, Space Processing of Materials, (12 July 1996); doi: 10.1117/12.244340

Published in SPIE Proceedings Vol. 2809:
Space Processing of Materials
Narayanan Ramachandran, Editor(s)