# Self-Diffusion in Simple Liquids as a Random Walk Process

## Abstract

**:**

## 1. Introduction

## 2. Results

#### 2.1. Diffusion as Random Walk

#### 2.2. Relation to Collective Modes Properties

## 3. Discussion and Conclusions

## Funding

## Institutional Review Board Statement

## Informed Consent Statement

## Data Availability Statement

## Conflicts of Interest

## Abbreviations

SE relation | Stokes–Einstein relation |

OCP | one-component plasma |

VDOS | vibrational density of states |

QLCA | quasi-localized charge approximation |

## Appendix A. Dispersion Relations of a Strongly Coupled OCP Fluid

$\langle {\mathit{\omega}}^{2}/{\mathit{\omega}}_{\mathbf{p}}^{2}\rangle $ | $\langle \mathit{\omega}/{\mathit{\omega}}_{\mathbf{p}}\rangle $ | $\langle \phantom{\rule{0pt}{0ex}}ln\mathit{\omega}/{\mathit{\omega}}_{\mathbf{p}}\rangle $ | $\langle {\mathit{\omega}}_{\mathbf{p}}/\mathit{\omega}\rangle $ | $\langle {\mathit{\omega}}_{\mathbf{p}}^{2}/{\mathit{\omega}}^{2}\rangle $ |
---|---|---|---|---|

$\frac{1}{3}$ | 0.514 | −0.8023 | 2.5856 | 9.7623 |

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**Figure 1.**(Color online) Stokes–Einstein parameter ${\alpha}_{\mathrm{SE}}$ as a function of the coupling parameter $\mathsf{\Gamma}$ for a OCP fluid. The symbols correspond to MD simulation results from Refs. [28,29]. The dashed line shows a strong coupling asymptote ${\alpha}_{\mathrm{SE}}\simeq 0.14$.

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**MDPI and ACS Style**

Khrapak, S.A.
Self-Diffusion in Simple Liquids as a Random Walk Process. *Molecules* **2021**, *26*, 7499.
https://doi.org/10.3390/molecules26247499

**AMA Style**

Khrapak SA.
Self-Diffusion in Simple Liquids as a Random Walk Process. *Molecules*. 2021; 26(24):7499.
https://doi.org/10.3390/molecules26247499

**Chicago/Turabian Style**

Khrapak, Sergey A.
2021. "Self-Diffusion in Simple Liquids as a Random Walk Process" *Molecules* 26, no. 24: 7499.
https://doi.org/10.3390/molecules26247499