Nucleation behavior investigation of cinnamic acid in pure organic solvents: Induction time, metastable zone width and molecular dynamics simulations.

• The nucleation behavior and nucleation kinetics of cinnamic acid were investigated and calculated. • Both the solute–solute and solute–solvent interactions during nucleation process were explored by molecular simulation. • The intrinsic mechanism of different solvents affecting the desolvation process was revealed. In this paper, the induction time and the metastable zone widths (MSZWs) of cinnamic acid in four pure solvents methanol, ethanol, acetone, and ethyl acetate were determined. Driven by the same supersaturation, the induction time is ethyl acetate > methanol > ethanol > acetone in descending order, then the effect of solvent on nucleation was further investigated by model fitting and molecular dynamic (MD) simulation. The MSZWs were fitted with the Nývlt's approach and Modified Sangwal's theory to investigate its nucleation kinetics. The results show that the fitted interfacial energy γ increases with decreasing saturation temperature and increasing cooling rate, which explains why nucleation is more likely to occur at high saturation temperatures and low cooling rates. Also, the pre-exponential factor A exhibits a strong correlation with the solvent and cooling rate. Further calculations of the key nucleation parameters (r crit , Δ G crit , J) show a positive relationship between the critical nucleation radius r crit and the critical Gibbs free energy Δ G crit. The nucleation rate J is equilibrated under the combined constraints of saturation temperature and driving force Δ µ. Finally, the intermolecular forces in the lattice were analyzed using Hirshfeld surface (HS) and 2D fingerprinting to probe the self-assembly process of molecules. And the hydrogen bonding sites between solute and solvent were predicted by molecular electrostatic potential surface (MEPs). The solute–solvent interaction was visualized by radial distribution function (RDF) and then quantified by calculating the interaction energy. The results show that the stronger hydrogen bonding interactions lead to lower nucleation rates, revealing the important role of solute–solute and solute–solvent interactions in solute desolvation and nucleation process. [ABSTRACT FROM AUTHOR]