Abstract
X-ray diffraction patterns of highly oriented samples of 4,4′-di-n-heptyl-azoxybenzene within the smectic state showed beside the intense first order reflection in the X-ray small angle region a new, unexpected fine structure:
(I) | Up to 6 sharp and distinct satellite reflections were detected in bz-direction, caused by a longitudinal modulation (static or dynamic) of the layered system. Their intensities were of the order of 1 to 3% of the main peak. | ||||
(II) | In the orthogonal direction, bx, only a continuous scattering was measured around the main peak, indicative of damped undulations of the layers. |
The distinct satellite reflections has been found stable within the whole temperature range of the smectic phase.