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Updated: Apr 22, 2026
High-Contrast and Fast Photorheological Switching of a Twist-Bend Nematic Liquid Crystal
Published on: October 31, 2019
Unveiling the Magnetic Ordering, Structural Phase Transition, Dynamical Stability, and Optoelectronic Properties of
Mahia Omar1, Mohannad Al-Hmoud2, Ghlamallah Benabdellah3
1Synthesis and Catalysis Laboratory, Department of Physic, Faculty of Matter Sciences, University of Tiaret, Tiaret, Algeria.
Abstract:
Fluoro-perovskites have attracted considerable attention due to their distinct and adjustable electronic, magnetic, and optical properties. In this work, a comprehensive first-principles study based on density functional theory is carried out to investigate the physical properties of NaCoF3 in the orthorhombic Pnma and Cmcm phases. The results reveal that the perovskite (Pnma) phase is the ground-state structure, exhibiting a G-type antiferromagnetic configuration. Enthalpy calculations indicate a pressure-induced phase transition to the post-perovskite (Cmcm) phase at a static pressure of 8.28 GPa at 0 K, with the stability domain of the post-perovskite phase decreasing as temperature increases. Phonon dispersion analysis confirms the dynamical stability of the Pnma phase, while the Cmcm phase is stable only under external thermodynamic conditions. The Co-3d orbitals are highly influenced by the correlation effects on the electronic structure. There is intense polarization and a high absorption in the 4.0-5.0-eV range, as well as a significant anisotropy in the dielectric function and refractive index. The structural stability, antiferromagnetic ordering, insulating behavior, and anisotropic optical response of NaCoF3 make it an interesting candidate in the formation of antiferromagnetic data-storage devices and ultraviolet optoelectronic applications.
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