Fast scanning calorimetry (FSC) was applied for measurements of the sublimation rates of theophylline, caffeine and anthraquinone as reference compounds. In comparison to conventional vapor pressure determination techniques, this method requires only nano-gram-size samples. The increased surface to volume ratio allows for very high sublimation rates and makes the sublimation process dominant over a possible decomposition. Experimental conditions and data treatment have been elaborated and validated by comparison with reliable literature data. The FSC method opens a new door for reliable experimental determination of vapor pressures and sublimation enthalpies for very low volatile and thermally unstable compounds like bio-relevant molecules.
Compounds
#
Formula
Name
1
C7H8N4O2
3,7-dihydro-1,3-dimethyl-1H-purine-2,6-dione
2
C8H10N4O2
caffeine
3
C14H8O2
9,10(9H,10H)-anthracenedione
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
Vapor or sublimation pressure, kPa ; Crystal
Temperature, K; Crystal
Crystal
Gas
Fast Scanning Calorimeter Method
30
POMD
1
Molar heat capacity at constant pressure, J/K/mol ; Crystal
Temperature, K; Crystal
Pressure, kPa; Crystal
Crystal
DSC
20
POMD
2
Vapor or sublimation pressure, kPa ; Crystal 1
Temperature, K; Crystal 1
Crystal 1
Gas
Fast Scanning Calorimeter Method
30
POMD
3
Vapor or sublimation pressure, kPa ; Crystal
Temperature, K; Crystal
Crystal
Gas
Fast Scanning Calorimeter Method
18
POMD
3
Molar heat capacity at constant pressure, J/K/mol ; Crystal