As a technology of separation and purification

crystallization plays a vital role in diverse industries such as inorganic salt

pharmaceutical

and food industries

which has a huge impact on purity

crystal polymorph

crystal morphology

and particle size distribution of final products. In the past few decades

with the rapid advancement of experimental approaches and molecular simulation methods

considerable advances in the interpretation of crystallization mechanisms have been obtained

promoting the investigation and understanding of crystallization theories greatly. In this review

the advances of pharmaceutical crystallization theories in recent years from the perspectives of nucleation and crystal growth are summarized and discussed. Two thermodynamic models that are helpful in the study of the crystallization mechanisms will be introduced. In this section

the perturbed-chain statistical associating fluid theory (PC-SAFT) and a chemical-potential-gradient model will be introduced

which have been successfully applied in pharmaceutical solubility prediction

the research of dissolution mechanism as well as dissolution kinetics analysis. These two models are expected to be applied to the study of pharmaceutical crystallization process and mechanism. Furthermore

molecular simulation based on the interaction between particles can provide structural information

thermodynamics

and dynamics properties of complex systems at the molecular level

like intermolecular interaction and surface adsorption energies. Application and some shortcomings of molecular simulation

especially molecular dynamics simulation

in the field of pharmaceutical crystallization will be expounded.