High-Pressure Nucleation of Low-Density Polymorphs

The crystallized above 0.3 GPa polymorphs β and γ of bis-3-nitrophenyl disulphide, are less dense than the ambient-pressure polymorph α. This high-entropy nucleation illustrates the molecular-scale mechanism of empirical Ostwald’s rule of stages. This method, in contrast to mechanochemical techniques, is ideally suited the kinetic nucleation of new low-density conformational polymorphs.