Additionally, parameters that should remain consistent between samples, such as the head binding enthalpy (∆𝐻 '($) ), were constrained in the optimization process. Through fitting this modified Ising model to the experimental data, thermodynamic constants were extracted (Table ) and the experimental data was simulated (Figure and). While fitting the previously employed Ising model Through a previous analysis of powder X-ray diffraction data, stearate capped indium phosphide quantum dots were found to have a sharper peak that was shifted towards smaller angles, compared to the myristate and palmitate capped quantum dots, indicating the existence of greater surface ligand ordering. However, once stearate capped nanocrystals are exchanged to contain 10% oleylamine, a bent ligand, the powder X-ray diffraction peak resembled that of myristate and palmitate capped quantum dots, indicating that there has been a structural change. To account for greater ordering in stearate ligand shells an additional phase transition term was introduced to the modeling process. Starting with the previously employed modified Ising model, an additional enthalpic penalty-as well as an entropic gain-was added when an indium stearate surrounded by other indium stearates was replaced by zinc chloride, to reflect an exchange in which the crystalline phase is disrupted. In subsequent exchanges where indium stearate is not surrounded by all similar neighbors, these additional terms are not accounted for because that ligand is not considered to be in the more crystalline phase. Of course, like all of the other modified Ising models used to model the ligand exchange on quantum dot surfaces, between isotropically distributed ligands, with a fixed ligand density, decreases (𝜃 " > 𝜃 , > 𝜃 -) causing an increase in inter-ligand interactions.