Short-range order structure and free volume distribution in liquid bismuth: X-ray diffraction and computer simulations studies

ABSTRACT

The structure of liquid bismuth was studied by X-ray diffraction and computer simulation methods. The contraction of the atomic structure within the first coordination sphere in the temperature interval of 575-1225 K is reported. The temperature dependencies of the coordination numbers and of the free volume are analysed. On the basis of the temperature dependencies of the free volume, the temperature dependencies of viscosity and the self-diffusion coefficient were calculated to be in the ranges from 1.17 to 0.86 mPa s and from 2.18 × 10⁻⁹ to 5.44 × 10⁻⁹ m²/s, respectively. The free volume – extracted results are in fair agreement with the experimental data and with the results obtained in the molecular dynamics simulations.

KEYWORDS:

• Liquid metals
• liquid bismuth
• viscosity coefficient
• self-diffusion coefficient
• free volume theory

Acknowledgements

The authors gratefully acknowledge the TASK Academic Computer Centre (Gdansk, Poland) for providing the computer time and the facilities.

Disclosure statement

No potential conflict of interest was reported by the author(s).