Critical Review on the Physical Properties of Gallium-Based Liquid Metals and Selected Pathways for Their Alteration

Gallium-based liquid metals have gained plenty of attention in the scientific community due to their extraordinary properties. The most intriguing properties of liquid metals are high surface tension, density anomaly, high electrical and thermal conductivity, phase transition, and their temperature and low viscosity in combination with their low toxicity. Though there are many reports of the physical properties of gallium-based liquid metals, some of these are highly scattered and inconsistent. Therefore, we compile literature data of these aspects of gallium-based liquid metals, point out general relationships of these physical parameters, and unravel inconsistencies in the literature. Subsequently, we state reasons for the observed scatter and recommend science-based values researchers should employ. Furthermore, we discuss important dependencies between the physical parameters, introduce methods to alter the physical parameters, and introduce selected applications based on changing the physical properties. Finally, we point out open questions concerned with the physical parameters of liquid metals, which should be investigated in the future.