# Fluid-Fluid Interfaces of Multi-Component Mixtures in Local Equilibrium

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## Abstract

**:**

## 1. Introduction

## 2. Excess Densities Defined

## 3. Thermodynamic Properties of Gibbs Surface

#### 3.1. The Interface at Global Equilibrium with the Surroundings

#### 3.2. The Interface Away from Global Equilibrium

## 4. Excess Densities and the Choice of Dividing Surface

## 5. The Autonomous Surface

#### 5.1. Invariance to Choice of Surface Location (Gauge Invariance)

#### 5.2. The Gibbs, Gibbs-Duhem, and Clapeyron Equations

## 6. Discussion and Conclusions

#### 6.1. Numerical Evidence for an Autonomous Interface

#### 6.2. Surface Properties and Surface Jumps

#### 6.3. Conclusions

## Acknowledgments

## Author Contributions

## Conflicts of Interest

## References

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Bedeaux, D.; Kjelstrup, S. Fluid-Fluid Interfaces of Multi-Component Mixtures in Local Equilibrium. *Entropy* **2018**, *20*, 250.
https://doi.org/10.3390/e20040250

**AMA Style**

Bedeaux D, Kjelstrup S. Fluid-Fluid Interfaces of Multi-Component Mixtures in Local Equilibrium. *Entropy*. 2018; 20(4):250.
https://doi.org/10.3390/e20040250

**Chicago/Turabian Style**

Bedeaux, Dick, and Signe Kjelstrup. 2018. "Fluid-Fluid Interfaces of Multi-Component Mixtures in Local Equilibrium" *Entropy* 20, no. 4: 250.
https://doi.org/10.3390/e20040250