Development of microcapsules for electron microscopy and their application to dynamical observation of liquid crystals in transmission electron microscopy

Microcapsules made of hard carbon films were fabricated for electron microscopic observations of liquid-like samples such as biological cells/molecules in water solution and liquid crystals. 4-(1-methylheptyloxycarbonyl) pheny1-4-octyloxybipheny1-4-carboxylate (MHPOBC) liquid crystals housed in the capsule were observed by transmission electron microscopy at 120 kV accelerating voltage. From the series of electron diffraction patterns, the rate of electron irradiation damage was estimated for the cases of changing sample temperature, beam current density and accelerating voltage. Phase transitions from a crystalline phase to liquid crystalline phases such as an isotropic-A phase of a smectic state (Sm-I-A) and a chiral-A phase of a smectic state (Sm-C-A*) were successfully observed and the rotation fluctuation of the molecules in the phase was measured by using the electron diffraction patterns.