# First-principles calculation of principal Hugoniot and K-shell X-ray absorption spectra for warm dense KCl

## Abstract

Principal Hugoniot and K-shell X-ray absorption spectra of warm dense KCl are calculated using the first-principles molecular dynamics (FPMD) method. Evolution of electronic structures as well as the influence of the approximate description of ionization on pressure (caused by the underestimation of the energy gap between conduction bands and valence bands) in the first-principles method are illustrated by the calculation. It is shown that approximate description of ionization in FPMD has small influence on Hugoniot pressure due to mutual compensation of electronic kinetic pressure and virial pressure. The calculation of X-ray absorption spectra shows that the band gap of KCl persists after the pressure ionization of the 3p electrons of Cl and K taking place at lower energy, which provides a detailed understanding to the evolution of electronic structures of warm dense matter.

- Authors:

- HEDPS, Center for Applied Physics and Technology, Peking University, Beijing 100871 (China)
- (China)
- Institute of Applied Physics and Computational Mathematics, Beijing 100088 (China)

- Publication Date:

- OSTI Identifier:
- 22490935

- Resource Type:
- Journal Article

- Resource Relation:
- Journal Name: Physics of Plasmas; Journal Volume: 22; Journal Issue: 6; Other Information: (c) 2015 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)

- Country of Publication:
- United States

- Language:
- English

- Subject:
- 75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; 70 PLASMA PHYSICS AND FUSION TECHNOLOGY; ABSORPTION SPECTRA; ELECTRONS; ENERGY GAP; K SHELL; MOLECULAR DYNAMICS METHOD; P STATES; POTASSIUM CHLORIDES; VALENCE; X-RAY SPECTRA

### Citation Formats

```
Zhao, Shijun, Zhang, Shen, Kang, Wei, E-mail: weikang@pku.edu.cn, College of Engineering, Peking University, Beijing 100871, Li, Zi, Zhang, Ping, Institute of Applied Physics and Computational Mathematics, Beijing 100088, He, Xian-Tu, E-mail: xthe@iapcm.ac.cn, College of Engineering, Peking University, Beijing 100871, and Institute of Applied Physics and Computational Mathematics, Beijing 100088.
```*First-principles calculation of principal Hugoniot and K-shell X-ray absorption spectra for warm dense KCl*. United States: N. p., 2015.
Web. doi:10.1063/1.4922672.

```
Zhao, Shijun, Zhang, Shen, Kang, Wei, E-mail: weikang@pku.edu.cn, College of Engineering, Peking University, Beijing 100871, Li, Zi, Zhang, Ping, Institute of Applied Physics and Computational Mathematics, Beijing 100088, He, Xian-Tu, E-mail: xthe@iapcm.ac.cn, College of Engineering, Peking University, Beijing 100871, & Institute of Applied Physics and Computational Mathematics, Beijing 100088.
```*First-principles calculation of principal Hugoniot and K-shell X-ray absorption spectra for warm dense KCl*. United States. doi:10.1063/1.4922672.

```
Zhao, Shijun, Zhang, Shen, Kang, Wei, E-mail: weikang@pku.edu.cn, College of Engineering, Peking University, Beijing 100871, Li, Zi, Zhang, Ping, Institute of Applied Physics and Computational Mathematics, Beijing 100088, He, Xian-Tu, E-mail: xthe@iapcm.ac.cn, College of Engineering, Peking University, Beijing 100871, and Institute of Applied Physics and Computational Mathematics, Beijing 100088. Mon .
"First-principles calculation of principal Hugoniot and K-shell X-ray absorption spectra for warm dense KCl". United States.
doi:10.1063/1.4922672.
```

```
@article{osti_22490935,
```

title = {First-principles calculation of principal Hugoniot and K-shell X-ray absorption spectra for warm dense KCl},

author = {Zhao, Shijun and Zhang, Shen and Kang, Wei, E-mail: weikang@pku.edu.cn and College of Engineering, Peking University, Beijing 100871 and Li, Zi and Zhang, Ping and Institute of Applied Physics and Computational Mathematics, Beijing 100088 and He, Xian-Tu, E-mail: xthe@iapcm.ac.cn and College of Engineering, Peking University, Beijing 100871 and Institute of Applied Physics and Computational Mathematics, Beijing 100088},

abstractNote = {Principal Hugoniot and K-shell X-ray absorption spectra of warm dense KCl are calculated using the first-principles molecular dynamics (FPMD) method. Evolution of electronic structures as well as the influence of the approximate description of ionization on pressure (caused by the underestimation of the energy gap between conduction bands and valence bands) in the first-principles method are illustrated by the calculation. It is shown that approximate description of ionization in FPMD has small influence on Hugoniot pressure due to mutual compensation of electronic kinetic pressure and virial pressure. The calculation of X-ray absorption spectra shows that the band gap of KCl persists after the pressure ionization of the 3p electrons of Cl and K taking place at lower energy, which provides a detailed understanding to the evolution of electronic structures of warm dense matter.},

doi = {10.1063/1.4922672},

journal = {Physics of Plasmas},

number = 6,

volume = 22,

place = {United States},

year = {Mon Jun 15 00:00:00 EDT 2015},

month = {Mon Jun 15 00:00:00 EDT 2015}

}