Construction of Ternary Phase Diagrams: Application of Quantitative NMR

The growth of cocrystalline phases continues to expand as a key area of crystal engineering research. Understanding the phase behavior of the material and controlling the crystalline form of the material from a solution-based route can be aided by the construction of a ternary phase diagram for the system. A range of methods exist for this process which display a variety of costs and time to achieve the final diagram. The application of quantitative NMR (qNMR) to this problem offers a fast analysis method to directly determine the solution composition of all species (coformers and solvent) and is demonstrated to successfully allow the construction of ternary diagrams with and without a cocrystal phase being formed for systems with high and low solubility.