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Updated: Apr 23, 2026

Characterization of Ultra-fine Grained and Nanocrystalline Materials Using Transmission Kikuchi Diffraction
Published on: April 1, 2017
Studying microstructure in molecular crystals with nanoindentation: intergrowth polymorphism in felodipine
Manish Kumar Mishra1, Gautam R Desiraju, Upadrasta Ramamurty
1Solid State and Structural Chemistry Unit, Indian Institute of Science, Bangalore 560012 (India).
Abstract:
Intergrowth polymorphism refers to the existence of distinct structural domains within a single crystal of a compound. The phenomenon is exhibited by form II of the active pharmaceutical ingredient felodipine, and the associated microstructure is a significant feature of the compound's structural identity. Employing the technique of nanoindentation on form II reveals a bimodal mechanical response on specific single-crystal faces, demonstrating distinct properties for two polymorphic forms within the same crystal.
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