Supporting information for: Towards understanding the thermodynamic viability of Zeolites and related frameworks through a simple topological model Martijn A. Zwijnenburg, Stefan T. Bromley, Martin D. Foster, Robert G. Bell, Olaf Delgado-Friedrichs, Jacobus C. Jansen, Thomas Maschmeyer S1 Applicability of the Sanders force field for calculating SiO 2 energetics To verify the applicability of the Sanders force field for calculating accurate values of the lattice enthalpies, we studied the correlation between the experimentally measured transition enthalpy by Piccione et al 1 and the calculated relative energies (using the Sanders forcefield 2, 3 ) for the zeolite frameworks: AFI, AST, CFI, CHA, FAU, FER, IFR, ITE, ISV, MEL, MTW, MWW and STT, and the dense silica polymorphs: Cristabolite and Tridymite. A linear least-squares fit (H exp =a*E calc +b) to the data points resulted in a fit with a correlation coefficient (r 2 ) of 0.84 and regression coefficients of a = 0.66 and b = 0.80. Fig. 1. The experimentally measured transition enthalpy versus the calculated relative energy for 13 zeolite frameworks and two dense silica polymorphs. The line shown is the best linear least-squares fit to the data points. 0 2 4 6 8 10 12 14 16 0 5 10 15 20 25 Calculated relative energy compared to quartz (kJ/mol) Measured transition enthalpy (kJ/mol)