Accurate Vapor Pressure Prediction for Large Organic Molecules: Application to Materials Utilized in Organic Light-Emitting Diodes

We present a theoretical
method based on molecular dynamics (MD)
simulations for the prediction of saturated vapor pressure of liquids
constituting of large organic molecules at various temperatures. The
approach is based on free energy calculations at a fixed temperature
and a subsequent Gibbs–Duhem integration over the interval
of temperatures. Results of the theoretical approach are compared
with experimental measurements for a set of six molecules utilized
in organic light-emitting diodes (OLEDs). Good correspondence of theoretical
and experimental results suggests the developed methodology as a useful
tool in various areas of molecular design, which require prediction
of vapor pressures for liquids of large and chemically diverse compounds.