The energetics of melting of Yb2O3 (Tfus 2707 +- 20 K) and Lu2O3 (Tfus 2762 +- 15 K) were studied experimentally by drop-and-catch (DnC) calorimetry and computationally by ab initio molecular dynamic (AI MD) techniques. Fusion enthalpies for Yb2O3 (102 +- 10) kJ*mol-1 and Lu2O3 (125 +- 10) kJ*mol-1 were derived from the steps in enthalpy increments from DnC experiments performed on liquid and solid samples laser heated in an argon flow. Fusion enthalpy values for Yb2O3 and Lu2O3 obtained from AI MD computations were 124 +- 2 kJ/mol and 124 +- 3 kJ/mol, respectively. High temperature heat capacity values for solid and liquid phases and volume change on melting were obtained from AI MD. Computed volume change on melting for both oxides is less than 1%, prompting an experimental investigation due to difference with prior experimental results. Experimental results indicate substantial dissolution of oxygen in liquid Lu2O3.
Compounds
#
Formula
Name
1
O3Yb2
ytterbium oxide (Yb2O3)
2
Lu2O3
lutetium oxide (Lu2O3)
Datasets
The table above is generated from the ThermoML associated json file (link above).
POMD and RXND refer to PureOrMixture and Reaction Datasets. The compound numbers are included in properties, variables, and phases, if specificied;
the numbers refer to the table of compounds on the left.
Type
Compound-#
Property
Variable
Constraint
Phase
Method
#Points
POMD
1
Molar enthalpy of transition or fusion, kJ/mol ; Crystal
Crystal
Liquid
Air at 1 atmosphere
Drop calorimetry
1
POMD
1
Molar enthalpy, kJ/mol ; Crystal
Temperature, K; Crystal
Pressure, kPa; Crystal
Crystal
Drop calorimetry
6
POMD
1
Molar enthalpy, kJ/mol ; Liquid
Temperature, K; Liquid
Pressure, kPa; Liquid
Liquid
Drop calorimetry
11
POMD
2
Molar enthalpy of transition or fusion, kJ/mol ; Crystal