Deorbitalized Meta-GGA with the Long Range van der Waals Exchange-Correlation Functional Calculations of the Insulator-Metal Transition of Hydrogen
J. Hinza , V.V. Karasieva , S.X. Hua , M. Zaghooa , and D. Mejia-Rodriguezb
aLaboratory for Laser Energetics, University of Rochester, Rochester, NY 14623-1299
bQuantum Theory Project, Department of Physics, University of Florida, Gainesville, Florida 32611
The insulator-metal (IM) transition of hydrogen is of great interest for both inertial confinement fusion experiments and H-He demixing associated with interior planetary processes. Accordingly, in this work we run ab-initio molecular dynamic (AIMD) simulations using the deorbitalized strongly constrained and appropriately normed (SCAN-L) meta-generalized gradient approximation exchange-correlation functional1 supplemented with the long-range van der Waals interaction from the revised Vydrov–van Voorhis nonlocal correlation (rVV10) (Ref 2).
The IM transition boundary is primarily determined via sudden slope changes of the reflectivity and minimum metal electrical conductivity calculated in the Kubo-Greenwood formalism along the isobars of pressure-temperature domain ranging from 30 to 300 GPa and 800 to 3000 K. Further calculations of the pair correlation function determine the level of disassociation of H2 to confirm the transition boundary location. The results of our calculations are in good agreement with the static compression experiments of Zaghoo et al3 and further confirm the possibility of a slope change in the phase boundary that appears both in experiments and in quantum Monte-Carlo simulations at approximately 1000 K and 280 GPa. Our work also indicates a convergence of SCAN-L+rVV10 with the standard Perdew-Burke-Ernzerhof (PBE) calculations only in the high-temperature, low-pressure region of the phase boundary.
This material is based upon work supported by the Department of Energy National Nuclear Security Administration under Award Number DE- NA0003856 and US National Science Foundation PHY Grant No. 1802964. DMR acknowledges support by US National Science Foundation Grant No. DMR-1515307.
1D. Mejía-Rodríguez and S. B. Trickey, Phys. Rev. A 96, 052512 (2017).
2R. Sabatini, T. Gorni, and S. de Gironcoli, Phys. Rev. B 87, 041108 (2013).
3M. Zaghoo and I. F. Silvera, Proc. Natl. Acad. Sci. 114, 11873-11877 (2017).