Crystal Morphology, Solubility, Optical and Nonlinear Optical Studies of DAST Crystals Grown from Different Solvents
Other Title
不同溶劑下DAST晶體生長的型態、溶解度及光學性質之研究
Journal
Journal of the Chinese Institute of Chemical Engineers
Journal Volume
33
Journal Issue
5
Start Page
461
End Page
468
ISSN
0368-1653
Date Issued
2002-09
Author(s)
Abstract
We report the solubility of DAST, an organic nonlinear optical material, in pure and mixed solvents at different temperatures. The metastable regions of the DAST solution in different solvents, saturated at a particular temperature, were studied. By applying the van’t Hoff equation, the enthalpy and the entropy of solutions were calculated. Crystals of different morphologies were harvested and studied to determine their various properties. The thermal and phase stability of the crystals was studied using a differential scanning calorimeter (DSC). The powder XRD and Kurtz powder techniques were used to assess the second harmonic generation (SHG) efficiency. The absorption spectrum showed different absorption cutoff wavelengths for SHG active and inactive DAST crystals.
本文中我們報導了高效能有機非線性光學DAST單晶，在不同混合溶劑下的溶解度曲線及界穩區。並借由van't Hoff方程，估算了溶劑的焓及熵。在不同溶劑下，晶體的型態有明顯的差異，我們並以DSC研究其熱及相的穩定性。經由XRD及粉末二倍頻的量測發現，含水的DAST長扁型結晶具有不同的結晶結構及遮斷吸收波長，且不具非線性光學活性。
Subjects
Nonlinear optical material
Mixed solvents
Morphology
Solubility
Heat of solution
Type
journal article