Similarly, below 1293 K, wurtzite (ZnS) is less stable than sphalerite (ZnS). In vacuum, wurtzite becomes more stable than sphalerite when the particle size is less than 7 nm at 300 K. At very small particle sizes, the addition of water to the surface of ZnS nanoparticles can induce a change in nanoparticle structure  and surface-surface interactions can drive a reversible structural transformation upon aggregation/disaggregation.
Similarly, below 1293 K, wurtzite (ZnS) is less stable than sphalerite (ZnS). In vacuum environments, wurtzite becomes more stable than sphalerite when the particle size is under 7 nm at 300 K. At very small sizes, changes in nanoparticle structure and surface interactions can lead to reversible structural transformations upon aggregation or disaggregation.