Polymorphism and crystal-crystal transformations of the highly optically nonlinear organic compound α-[(4’-methoxyphenyl)methylene]-4-nitro-benzeneacetonitrile.

Autor: Oliver, S. N., Pantelis, P., Dunn, P. L.
Předmět:
Zdroj: Applied Physics Letters; 1/22/1990, Vol. 56 Issue 4, p307, 3p
Abstrakt: Crystals of α-[(4’-methoxyphenyl)methylene]-4-nitro-benzeneacetonitrile exhibit powder second-harmonic generation (SHG) efficiencies under 1.06 μm irradiation several times that of 2-methyl-4-nitroaniline. We have identified three distinct, solution-grown polymorphs which show marked variation in SHG efficiency. Controlled transformation between these polymorphs can be made either solvent assisted or thermally. One polymorph shows a 25-fold increase in SHG efficiency when the irradiation wavelength is changed to 1.32 μm while the others show a small or no increase. [ABSTRACT FROM AUTHOR]
Databáze: Complementary Index