Molecular dynamics studies of melting and some liquid-state properties
of 1-ethyl-3-methylimidazolium hexafluorophosphate emimPF6.
J. Chem. Phys., 122 (15):
154704 (апреля 2005)DOI: 10.1063/1.1880932
Аннотация
Molecular dynamics simulations are used to study the liquid-state
properties and melting of 1-ethyl-3-methylimidazolium hexafluorosphosphate
emimPF6 using the force field of Canongia Lopes et al. J. Phys.
Chem. B 108, 2038 (2004) and geometric constants from crystallographic
data. The structures of the solid and liquid states are characterized
by carbon-carbon, carbon-phosphorous, and phosphorous-phosphorous
radial distribution functions. Spatial correlations among the ions
are strong in the liquid state. The cohesive energy density and the
temperature dependences of the molar volume and density of the liquid
have been computed. The melting point is determined by equilibrating
the solid-state supercells in which void defects have been introduced
to eliminate the free-energy barrier for the formation of a solid-liquid
interface. The computed melting point is 375+/-10 K, which is approximately
10\% higher than the experimental value of 333 K.