Crystal structures and electronic properties of solid fluorine under high pressure
Lv Qianqian, Jin Xilian †, Cui Tian ‡, Zhuang Quan, Li Ying, Wang Youchun, Bao Kuo, Meng Xing
       

Calculated phonon dispersion curves for (a) C2/m at 0 GPa, (b) C2/c at 0 GPa, and (c) Cmca at 100 GPa.