ABSTRACT

A quick and accurate methodology that is based on Langmuir's equation and that is developed by utilising a DSC7 device is proposed for the measurement of the enthalpies of sublimation of substances characterised by vapour pressures of approximately 1.0 Pa at room temperature. The procedure was applied to ferrocene and nickelocene; the accuracy and uncertainty associated with the experimental results show that the reliability of the developed indirect method is comparable to the direct calorimetric measurements also performed in this work. Furthermore, the melting data and crystal-phase heat capacities for both metallocenes were calorimetrically measured, whereas the gas-phase heat capacity for each metallic bis(cyclopentadienyl) was theoretically estimated by DFT calculations.

Compounds

#	Formula	Name
1	C10H10Fe	ferrocene
2	C10H10Ni	nickelocene

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	DSC	1
POMD	1	Normal melting temperature, K ; Crystal			Crystal Liquid Air at 1 atmosphere	DTA	1
POMD	1	Molar enthalpy of vaporization or sublimation, kJ/mol ; Crystal	Temperature, K; Crystal		Crystal Gas	DSC	1
POMD	1	Molar enthalpy of vaporization or sublimation, kJ/mol ; Crystal	Temperature, K; Crystal		Crystal Gas	Static calorimetry	1
POMD	1	Molar heat capacity at constant pressure, J/K/mol ; Crystal	Temperature, K; Crystal	Pressure, kPa; Crystal	Crystal	Small sample (50 mg) DSC	62
POMD	1	Molar heat capacity at constant pressure, J/K/mol ; Gas	Temperature, K; Gas	Pressure, kPa; Gas	Gas	Small sample (50 mg) DSC	61
POMD	2	Molar enthalpy of transition or fusion, kJ/mol ; Crystal			Crystal Liquid Air at 1 atmosphere	DSC	1
POMD	2	Normal melting temperature, K ; Crystal			Crystal Liquid Air at 1 atmosphere	DTA	1
POMD	2	Molar enthalpy of vaporization or sublimation, kJ/mol ; Crystal	Temperature, K; Crystal		Crystal Gas	DSC	1
POMD	2	Molar enthalpy of vaporization or sublimation, kJ/mol ; Crystal	Temperature, K; Crystal		Crystal Gas	Static calorimetry	1
POMD	2	Molar heat capacity at constant pressure, J/K/mol ; Crystal	Temperature, K; Crystal	Pressure, kPa; Crystal	Crystal	Small sample (50 mg) DSC	62
POMD	2	Molar heat capacity at constant pressure, J/K/mol ; Gas	Temperature, K; Gas	Pressure, kPa; Gas	Gas	Small sample (50 mg) DSC	61

Thermodynamics Research Center / ThermoML | Journal of Chemical Thermodynamics

Enthalpies of sublimation of ferrocene and nickelocene measured by calorimetry and the method of Langmuir

Rojas, A.[Aaron], Vieyra-Eusebio, M. T.[Maria Teresa]

ABSTRACT