Dynamics of the investigated MOFs were simulated between 40-400 K, with 20 K increases in temperature, and average cell parameters were computed. As displayed in the Electronic Supplementary Information (ESI), each of the MOFs exhibit considerable contraction in response to heating, and no significant changes to the unit cell shapes were observed. This contraction produces pronounced NTE, Figure , with frameworks displaying a change in volume between 1-3 %. In general, NTE materials show total volume contractions <1.5 %, making the magnitude of contraction observed by these materials exceptional. The volumetric thermal expansion coefficient (α V ), defined in Equation , provides a measure of the expansion rate.