Fig. 1: Calculated versus reference pressure-dependent part of the chemical potential of water at phase transition.
From: Predicting crystal form stability under real-world conditions

The relative humidity (RH) is shown on the secondary axes. Reference systems excluded from the calculation of statistical errors because of ambiguities in experimental data are shown with open markers and dotted error bars. Error bars represent 1 standard error. R is the universal gas constant, T is the absolute temperature, aw is water activity and \({p}_{{\rm{w}}}^{{\rm{s}}{\rm{a}}{\rm{t}}}\) is the saturated vapor pressure of water. PPA, pipedimic acid; TETA, triethylenetetramine dichloride.