449 / 2019-03-08 10:16:04

Nitrogen at extremes

Nitrogen; high pressure and high temperature; Raman scattering; Laser heating diamond-anvil cell (LHDAC); Symmetry breaking.

全体主题 > High Pressure Physics and Materials Science

Nitrogen exhibits complicated phase behaviors at extremes. Pressure-induced intermolecular and intramolecular dissociative transitions in nitrogen molecules lead to rich solid molecular polymorphous (β, δ, δloc, , ζ, ζ’, , ι, λ and ) and polymeric phases (cg-N, LP-N and HLPN), respectively. We have accessed all the reported molecular solids of nitrogen by compressing nitrogen up to 200 GPa at ambient temperature or at low temperature. We also have synthesized cg-N and LP-N at 109-170 GPa and 1500-3000 K using a custom-built double-side laser heating diamond-anvil cell (LHDAC) without any laser absorbing material. In this presentation, I will introduce our recent advances in high-pressure nitrogen, and I will demonstrated a path from dense molecular fluid nitrogen to fully polymeric phases by breaking structural and polarization reversal symmetry.