ABSTRACT

Thermodynamic functions for 1-butyl-3-methylimidazolium hexafluorophosphate ([C4mim][PF6]) were reported in a range of temperatures from (5 to 550) K, based on new measurements by calorimetry. Heat capacities of the crystal, glass and liquid phases for [C4mim][PF6] were measured with a pair of calorimeters. A vacuum-jacketed adiabatic calorimeter was used at temperatures between (5 and 310) K and a triple-heat bridge scanning calorimeter was used from (300 to 550) K. With the adiabatic calorimeter, both the fusion temperature (283.51 K) and enthalpy (19.60 kJ.mol-1) and the glass transition temperature (190.6 K) were observed. The purity of the [C4mim][PF6] sample was determined to be 99.56 mol % by a fractional melting analysis. Densities of the liquid were measured in a range of temperatures from (298 to 353) K with a pycnometer equipped with a capillary neck. An unexpected endothermal transition, with a very small enthalpy change of 0.25 J?g-1 (0.071 kJ?mol-1) was observed in a range of temperatures from (394 to 412) K. Heat capacity jumps were determined at the glass transition, 81.6 J.K-1.mol-1, and fusion, 44.8 J.K-1.mol-1, and the observed entropy change at fusion is 69.23 J.K-1.mol-1.

Compounds

#	Formula	Name
1	C8H15F6N2P	1-butyl-3-methylimidazolium hexafluorophosphate

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 Gas	ADIACA:UFactor:2	1
POMD	1	Triple point temperature, K ; Crystal			Crystal Liquid Gas	ADIACA:UFactor:2	1
POMD	1	Triple point temperature, K ; Glass			Glass Liquid Gas	Adiabatic calorimetry	1
POMD	1	Molar heat capacity at constant pressure, J/K/mol ; Liquid	Temperature, K; Liquid	Pressure, kPa; Liquid	Liquid	heat bridge-scanning calorimeter	1528
POMD	1	Molar heat capacity at saturation pressure, J/K/mol ; Crystal	Temperature, K; Crystal		Crystal Gas	Small (less than 1 g) adiabatic calorimetry	137
POMD	1	Molar heat capacity at saturation pressure, J/K/mol ; Liquid	Temperature, K; Liquid		Liquid Gas	Small (less than 1 g) adiabatic calorimetry	42
POMD	1	Molar heat capacity at saturation pressure, J/K/mol ; Glass	Temperature, K; Glass		Glass Gas	Small (less than 1 g) adiabatic calorimetry	111
POMD	1	Molar heat capacity at saturation pressure, J/K/mol ; Crystal	Temperature, K; Crystal		Crystal Gas	Small (less than 1 g) adiabatic calorimetry	34
POMD	1	Molar heat capacity at saturation pressure, J/K/mol ; Liquid	Temperature, K; Liquid		Liquid Gas	Small (less than 1 g) adiabatic calorimetry	28
POMD	1	Molar heat capacity at saturation pressure, J/K/mol ; Glass	Temperature, K; Glass		Glass Gas	Small (less than 1 g) adiabatic calorimetry	25
POMD	1	Molar enthalpy function {Hm(T)-Hm(0)}/T, J/K/mol ; Crystal	Temperature, K; Crystal	Pressure, kPa; Crystal	Crystal	Small (less than 1 g) adiabatic calorimetry	34
POMD	1	Molar enthalpy function {Hm(T)-Hm(0)}/T, J/K/mol ; Liquid	Temperature, K; Liquid	Pressure, kPa; Liquid	Liquid	Small (less than 1 g) adiabatic calorimetry	28
POMD	1	Molar entropy, J/K/mol ; Crystal	Temperature, K; Crystal	Pressure, kPa; Crystal	Crystal	Small (less than 1 g) adiabatic calorimetry	34
POMD	1	Molar entropy, J/K/mol ; Liquid	Temperature, K; Liquid	Pressure, kPa; Liquid	Liquid	Small (less than 1 g) adiabatic calorimetry	28
POMD	1	Mass density, kg/m3 ; Liquid	Temperature, K; Liquid	Pressure, kPa; Liquid	Liquid	Pycnometric method	10

Thermodynamics Research Center / ThermoML | Journal of Chemical and Engineering Data

Thermodynamic Properties of 1-Butyl-3-methylimidazolium Hexafluorophosphate in the Condensed State

Kabo, G. J., Blokhin, A. V.[Andrey V.], Paulechka, Y. U.[Yauheni U.], Kabo, A. G.[Andrey G.], Shymanovich, M. P.[Marina P.], Magee, J. W.[Joseph W.]

ABSTRACT