All Optical Determination of Microscopic and Macroscopic Structure of Chiral, Polar Microcrystals from Achiral, Nonpolar Molecules

作者：Van Cleuvenbergen Stijn^*; Hennrich Gunther; Willot Pieter; Koeckelberghs Guy; Clays Koen; Verbiest Thierry; van der Veen Monique A

来源：Journal of Physical Chemistry C, 2012, 116(22): 12219-12225.

DOI：10.1021/jp302665t

Organic microcrystals obtained from an octupolar molecule are studied by polarized nonlinear optical microscopy. While two-photon fluorescence microscopy is employed to verify the monocrystallinity of the analyzed domains, second-harmonic generation microscopy allowed determination of the point group symmetry of the crystallites. This combined analysis revealed that the achiral, octupolar molecules form chiral and polar conglomerate structures; the former are confirmed by circular dichroism spectroscopy. We additionally present a convenient and straightforward image analysis protocol, based on polarization dependent second-harmonic generation microscopy. This allows assessing the local organization and homogeneity of crystalline structures, which is highly relevant for technological applications, with high resolution and sensitivity.

• 出版日期2012-6-7