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## Quantum molecular dynamics of warm dense iron and a five-phase equation of state

## Abstract

Through quantum molecular dynamics (QMD), utilizing both Kohn-Sham (orbital-based) and orbital-free density functional theory, we calculate the equation of state of warm dense iron in the density range 7–30/ cm ^{3} and temperatures from 1 to 100 eV. A critical examination of the iron pseudopotential is made, from which we find a significant improvement at high pressure to the previous QMD calculations of Wang et al. [Phys. Rev. E 89, 023101 (2014)]. Here, our results also significantly extend the ranges of density and temperature that were attempted in that prior work. We calculate the shock Hugoniot and find very good agreement with experimental results to pressures over 20 TPa. Finally, these results are then incorporated with previous studies to generate a five-phase equation of state for iron.

- Authors:

- Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

- Publication Date:

- Research Org.:
- Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

- Sponsoring Org.:
- USDOE National Nuclear Security Administration (NNSA)

- OSTI Identifier:
- 1511602

- Alternate Identifier(s):
- OSTI ID: 1438959

- Report Number(s):
- LA-UR-17-28620

Journal ID: ISSN 2470-0045; PLEEE8

- Grant/Contract Number:
- 89233218CNA000001; AC52-06NA25396

- Resource Type:
- Accepted Manuscript

- Journal Name:
- Physical Review E

- Additional Journal Information:
- Journal Volume: 97; Journal Issue: 5; Journal ID: ISSN 2470-0045

- Publisher:
- American Physical Society (APS)

- Country of Publication:
- United States

- Language:
- English

- Subject:
- 75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY

### Citation Formats

```
Sjostrom, Travis, and Crockett, Scott. Quantum molecular dynamics of warm dense iron and a five-phase equation of state. United States: N. p., 2018.
Web. doi:10.1103/PhysRevE.97.053209.
```

```
Sjostrom, Travis, & Crockett, Scott. Quantum molecular dynamics of warm dense iron and a five-phase equation of state. United States. doi:10.1103/PhysRevE.97.053209.
```

```
Sjostrom, Travis, and Crockett, Scott. Thu .
"Quantum molecular dynamics of warm dense iron and a five-phase equation of state". United States. doi:10.1103/PhysRevE.97.053209.
```

```
@article{osti_1511602,
```

title = {Quantum molecular dynamics of warm dense iron and a five-phase equation of state},

author = {Sjostrom, Travis and Crockett, Scott},

abstractNote = {Through quantum molecular dynamics (QMD), utilizing both Kohn-Sham (orbital-based) and orbital-free density functional theory, we calculate the equation of state of warm dense iron in the density range 7–30/ cm3 and temperatures from 1 to 100 eV. A critical examination of the iron pseudopotential is made, from which we find a significant improvement at high pressure to the previous QMD calculations of Wang et al. [Phys. Rev. E 89, 023101 (2014)]. Here, our results also significantly extend the ranges of density and temperature that were attempted in that prior work. We calculate the shock Hugoniot and find very good agreement with experimental results to pressures over 20 TPa. Finally, these results are then incorporated with previous studies to generate a five-phase equation of state for iron.},

doi = {10.1103/PhysRevE.97.053209},

journal = {Physical Review E},

number = 5,

volume = 97,

place = {United States},

year = {2018},

month = {5}

}

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