The accuracy is actually slightly better for DDEC3, with a decrease in both density and heat of vaporisation errors, compared to the baseline model 0. DDEC6 has several methodological improvements, which are summarised elsewhere and have been shown to result in more robust convergence, lower computation times, lower ESP errors, and higher transferability, when compared to DDEC3. However, most of these advantages will not be apparent in the small, relatively rigid, organic molecules, which lack buried atoms and are simulated here under standard conditions.