Petryk I, Lutsiuk Y, Kramar V. Frequency spectrum and group velocities of acoustic phonons in PbI2 nanofilms. Phys. Chem. Sol. State [Internet]. 2022 Aug. 24 [cited 2024 May 3];23(3):478-83. Available from: https://scijournals.pnu.edu.ua/index.php/pcss/article/view/5733