Journal Papers

Su, Yan

Zhao, JJ (reprint author), Dalian Univ Technol, Minist Educ, Key Lab Mat Modificat Laser Electron & Ion Beams, Dalian 116024, Peoples R China.

Fan, Junyu,Zheng, Zhaoyang,Zhao, Jijun

2019-06-01

PROGRESS IN NATURAL SCIENCE-MATERIALS INTERNATIONAL

SCIE

J

29

3,SI

329-334

1002-0071

1,1-Diamino-2; 2-Dinitroethene; Anisotropic behavior; Raman spectra; Phase transformation

Using dispersion-corrected density functional theory (DFT), we investigate the effect of uniaxial compression on 1, 1-diamino-2, 2-dinitroethene (FOX-7) crystal. Principal and shear stresses along the [100], [010], and [001] orientations exhibit considerable anisotropic compressibility. Raman spectra are complemented by DFT calculations in vibrational modes. Several abnormal pressure-induced changes in selected Raman modes are observed along the [100] orientation. Combined Raman peak shifts with inter/intra-molecular hydrogen bonds and N-H/N-O covalent bonds, the results demonstrate that the spectroscopic variation are associated with the rearrangement of hydrogen-bonded networks of FOX-7 crystal. These findings imply a possible phase transformation or some minor changes in molecular conformation in the pressure regions under uniaxial compression.