Elucidation of Polymorph Mixtures Using Solid-State 13C CP/MAS NMR Spectroscopy and Direct Exponential Curve Resolution Algorithm

Polymorphic behavior has a broad impact on chemical technology influencing the solid-state properties of many materials from pigments to pharmaceuticals. The simultaneous presence of two or more polymorphs may introduce ambiguities in the characterization of materials using spectroscopy, diffraction, or scattering techniques. In this paper we present a solid-state 13C NMR method, together with the recently published direct exponential curve resolution algorithm, allows the elucidation of component spectra from the total spectrum of a mixture of polymorphs, previously characterized by X-ray diffraction.