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Updated: Feb 4, 2026
Methods of Ex Situ and In Situ Investigations of Structural Transformations: The Case of Crystallization of Metallic Glasses
Published on: June 7, 2018
Phase transformation in the C form of myristic-acid crystals and DFT calculations
J R S Miranda1, A J R de Castro2, J G da Silva Filho3
1Instituto de Ciências Exatas e Naturais, Universidade Federal do Pará, CEP 66075-110 Belém, PA, Brazil.
Abstract:
In this study, the vibrational frequencies of myristic acid (CH3(CH2)12COOH) were obtained using density functional theory calculations, and the results were compared with experimental Raman and infrared data. Additionally, Raman spectra of crystalline myristic acid were recorded in the 300-20 K range. Raman spectroscopy gives important insights into the effect of low temperatures on its monoclinic phase. X-ray diffraction was performed from 298 to 133 K to provide additional information about the cryogenic behavior of the crystals. These undergo a phase transformation, which was confirmed by differential scanning calorimetry through an enthalpy anomaly observed at low temperatures. Raman spectra and X-ray diffraction refinement of the cell parameters in combination with differential scanning calorimetry at low temperatures revealed slight modifications, confirming a conformational change in the myristic acid molecules involving rearrangement of dimers within the unit cell.
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