Structural, electronic, optical and thermodynamic investigations of NaXF 3 (X = Ca and Sr): First-principles calculations by Benkabou, M.H., Harmel, M., Haddou, A., Yakoubi, Abdelkader, Baki, N., Ahmed, Rashid, Al-Douri, Yarub, Syrotyuk, Stepan V., Khachai, Houari, Khenata, Rabah, Voon, Chun Hong, Johan, Mohd Rafie