The effect of hydrostatic pressure on the structure of solid phenanthrene (C14H10) was investigated up to 25.7 GPa through synchrotron X-ray powder diffraction and an evolutionary algorithm for crystal structure prediction based on van der Waals density functional calculations. We observed the onset of a phase transition around 8 GPa from the monoclinic P21 low-pressure phase with two molecules per unit cell arranged in a herringbone fashion to a new high-pressure phase. The best candidate structure for this phase exhibits three molecules in a P1 triclinic unit cell in a parallel arrangement, stabilized by dominant π–π intermolecular interactions. The P21 and P1 phases coexist in the pressure range from 8 to 13 GPa, whereas above 13 GPa only the P1 high-pressure phase is present. At higher pressures (P > 20 GPa), experiments and first-principles calculations suggest a tendency toward amorphization.
|Journal||The journal of physical chemistry (Washington, DC) / C|
|Publication status||Published - 2016|
Fields of Expertise
- Advanced Materials Science
Capitani, F., Hoeppner, M., Malavasi, L., Artioli, G. A., Marini, C., Hanfland, M., ... Postorino, P. (2016). Structural Evolution of Solid Phenanthrene at High Pressures. The journal of physical chemistry (Washington, DC) / C, 120, 14310-14316. https://doi.org/http://pubs.acs.org/doi/abs/10.1021/acs.jpcc.6b04326