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Updated: Jul 17, 2025

Comprehensive Characterization of Extended Defects in Semiconductor Materials by a Scanning Electron Microscope
Published on: May 28, 2016
Lattice Defects in Sub-Micrometer Spin-Crossover Crystals Studied by Electron Diffraction
Hilaire Mba1, Matthieu Picher1, Nathalie Daro2
1Institut de Physique et Chimie des Matériaux, UMR 7504, Université de Strasbourg, CNRS, 67034 Strasbourg, France.
Abstract:
Spin-crossover particles of [Fe(Htrz)2trz](BF4) with sizes of some hundred nanometers are studied by in situ electron microscopy. Despite their high radiation sensitivity, it was possible to analyze the particles by imaging and diffraction so that a detailed analysis of crystallographic defects in individual particles became possible. The presence of one or several tilt boundaries, where the tilt axis is the direction of the polymer chains, is detected in each particle. An in situ exposure of the particles to temperature variations or short laser pulses to induce the spin crossover shows that the defect structure only changes after a high number of transformations between the low-spin and high-spin phases. The observations are explained by the anisotropy of the atomic architecture within the crystals, which facilitates defects between weakly linked crystallographic planes.
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