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A thermal imaging furnace (TIF) was used to study the physical properties of molten Sc$$_{2}$$ 2 O$$_{3}$$ 3 , La$$_{2}$$ 2 O$$_{3}$$ 3 , Y$$_{2}$$ 2 O$$_{3}$$ 3 , Al$$_{2}$$ 2 O$$_{3}$$ 3 and MgO via a containerless method. The density and surface tension of molten droplets of Sc$$_{2}$$ 2 O$$_{3}$$ 3 , La$$_{2}$$ 2 O$$_{3}$$ 3 , Y$$_{2}$$ 2 O$$_{3}$$ 3 , Al$$_{2}$$ 2 O$$_{3},$$ 3 , and MgO suspended from their own solid were measured in situ using live video under a range of oxygen partial pressures (1$$\rightarrow $$ → 10$$^{-6}$$ - 6 atm O$$_{2}$$ 2 ). To the best knowledge of the authors, this is the first time the surface tension and density of molten MgO and Sc$$_{2}$$ 2 O$$_{3}$$ 3 have been reported. A relationship between molten oxide surface tension and the enthalpy of vaporization is proposed, and a comparison is drawn between the oxide properties and similar relationships previously established for liquid metals.

VO 2 experiences a metal-insulator transition at 340 K. Discontinuities in electronic transport properties, such as the Seebeck coefficient and the electronic conductivity, suggest that there is a significant change in the electronic structure upon metallization. However, the thermodynamic nature of this transformation remains difficult to describe using conventional computational and experimental methods. This has led to disagreement over the relative importance of the change in electronic entropy with respect to the overall transition entropy. A method is presented that links measurable electronic transport properties to the change in electronic state entropy of conduction electrons. The change in electronic entropy is calculated to be 9.2 ± 0.7 J/mol K which accounts for 62%-67% of the total transition entropy. This compares favorably with some estimates of the vibrational entropy.

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