*2.7. Dynamic Vapor Sorption (DVS)*

The critical relative humidity (RH) where the hydration of the anhydrous DIC-Na AH occurs was determined by dynamic vapor sorption (DVS) using a Dynamic Vapor Sorption Advantage instrument (Surface Measurement Systems Ltd., Wembley, UK) at 25 ◦C. The RH was increased from 0% to 90% and then decreased to 0% with a step width of 5%.
