ABSTRACT

The phase transitions of even n-alkanes, n-C34H70, n-C36H74, n-C40H82 and n-C42H86 with high purity have been measured using a high resolution and super-sensitive DSC. A new transition in the low temperature phase was observed in all the samples in the heating run. The surface freezing phenomenon was observed by thermal measurement for the first time in all the samples both in the heating and in the cooling run. The difference of the thermal behaviors between the heating and cooling run was also observed in all the samples.

Compounds

#	Formula	Name
1	C34H70	tetratriacontane
2	C36H74	hexatriacontane
3	C40H82	tetracontane
4	C42H86	dotetracontane

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	Phase	Method	#Points
POMD	1	Molar enthalpy of transition or fusion, kJ/mol ; Crystal 1	Crystal 1 Liquid Air at 1 atmosphere	DSC	1
POMD	1	Molar enthalpy of transition or fusion, kJ/mol ; Crystal 2	Crystal 2 Crystal 1 Air at 1 atmosphere	DSC	1
POMD	1	Molar enthalpy of transition or fusion, kJ/mol ; Crystal 3	Crystal 3 Crystal 2 Air at 1 atmosphere	DSC	1
POMD	1	Triple point temperature, K ; Crystal 1	Crystal 1 Liquid Air at 1 atmosphere	DTA	1
POMD	1	Triple point temperature, K ; Crystal 2	Crystal 2 Crystal 1 Air at 1 atmosphere	DTA	1
POMD	1	Triple point temperature, K ; Crystal 3	Crystal 3 Crystal 2 Air at 1 atmosphere	DTA	1
POMD	2	Molar enthalpy of transition or fusion, kJ/mol ; Crystal 1	Crystal 1 Liquid Air at 1 atmosphere	DSC	1
POMD	2	Molar enthalpy of transition or fusion, kJ/mol ; Crystal 2	Crystal 2 Crystal 1 Air at 1 atmosphere	DSC	1
POMD	2	Molar enthalpy of transition or fusion, kJ/mol ; Crystal 3	Crystal 3 Crystal 2 Air at 1 atmosphere	DSC	1
POMD	2	Molar enthalpy of transition or fusion, kJ/mol ; Crystal 4	Crystal 4 Crystal 3 Air at 1 atmosphere	DSC	1
POMD	2	Triple point temperature, K ; Crystal 1	Crystal 1 Liquid Air at 1 atmosphere	DTA	1
POMD	2	Triple point temperature, K ; Crystal 2	Crystal 2 Crystal 1 Air at 1 atmosphere	DTA	1
POMD	2	Triple point temperature, K ; Crystal 3	Crystal 3 Crystal 2 Air at 1 atmosphere	DTA	1
POMD	2	Triple point temperature, K ; Crystal 4	Crystal 4 Crystal 3 Air at 1 atmosphere	DTA	1
POMD	3	Molar enthalpy of transition or fusion, kJ/mol ; Crystal 1	Crystal 1 Liquid Air at 1 atmosphere	DSC	1
POMD	3	Molar enthalpy of transition or fusion, kJ/mol ; Crystal 2	Crystal 2 Crystal 1 Air at 1 atmosphere	DSC	1
POMD	3	Molar enthalpy of transition or fusion, kJ/mol ; Crystal 3	Crystal 3 Crystal 2 Air at 1 atmosphere	DSC	1
POMD	3	Triple point temperature, K ; Crystal 1	Crystal 1 Liquid Air at 1 atmosphere	DTA	1
POMD	3	Triple point temperature, K ; Crystal 2	Crystal 2 Crystal 1 Air at 1 atmosphere	DTA	1
POMD	3	Triple point temperature, K ; Crystal 3	Crystal 3 Crystal 2 Air at 1 atmosphere	DTA	1
POMD	4	Molar enthalpy of transition or fusion, kJ/mol ; Crystal 1	Crystal 1 Liquid Air at 1 atmosphere	DSC	1
POMD	4	Molar enthalpy of transition or fusion, kJ/mol ; Crystal 2	Crystal 2 Crystal 1 Air at 1 atmosphere	DSC	1
POMD	4	Molar enthalpy of transition or fusion, kJ/mol ; Crystal 3	Crystal 3 Crystal 2 Air at 1 atmosphere	DSC	1
POMD	4	Triple point temperature, K ; Crystal 1	Crystal 1 Liquid Air at 1 atmosphere	DTA	1
POMD	4	Triple point temperature, K ; Crystal 2	Crystal 2 Crystal 1 Air at 1 atmosphere	DTA	1
POMD	4	Triple point temperature, K ; Crystal 3	Crystal 3 Crystal 2 Air at 1 atmosphere	DTA	1

Thermodynamics Research Center / ThermoML | Thermochimica Acta

Observation of multiple phase transitions in some even n-alkanes using a high resolution and super-sensitive DSC

Wang, S., Tozaki, K.-I.[Ken-Ichi], Hayashida, H.[Hiromichi], Inaba, H.[Hideo], Yamamotoc, H.[Hiroko]

ABSTRACT