Dias, Ranga P.Noked, OriSilvera, Isaac2016-11-082016Dias, Ranga P., Ori Noked, and Isaac F. Silvera. 2016. “New Phases and Dissociation-Recombination of Hydrogen Deuteride to 3.4 Mbar.” Physical Review Letters 116 (14) (April 8). doi:10.1103/physrevlett.116.145501.0031-9007http://nrs.harvard.edu/urn-3:HUL.InstRepos:29374824We present infrared absorption studies of solid hydrogen deuteride to pressures as high as 340 GPa (100 GPa ¼ 1 Mbar) in a diamond anvil cell and temperatures in the range 5–295 K. Above 198 GPa the HD sample transforms to a mixture of HD, H2, and D2, interpreted as a process of dissociation and recombination. Three new phase lines are observed, two of which differ remarkably from those of the high pressure homonuclear species, but none are metallic. The time-dependent spectral changes are analyzed to determine the molecular concentrations as a function of time; the nucleon exchange achieves steady state concentrations in ∼20 h at ∼200 GPa.en-USJournal Article2016-11-0810.1103/PhysRevLett.116.145501