I have talked before about hydrogen bonds and their importance in water in:
Water’s Wide Range of Properties
as it is these quite rare intermolecular forces that give water its unique physical and chemical properties. These hydrogen bonds make the water (in its low density state) form tetrahedral patterns which exist suspended throughout the liquid. But to study the effect of these bonds in water, researchers managed to force the hydrogen bonds only to exist in two dimensions, essentially a flat sheet of water. This is the first paper to go very deeply into the behavior of hydrogen bonds in reduced dimensions and what effects this has on the physics of water in two dimensions as well. It was shown that the same results I described in the article above still apply. There were clusters of high and low density water molecules where the more hydrogen bonds actually decreased the density. Mathematical estimates for the specific heat capacity and enthalpy change within the two dimensional water were also made and these are definitely robust for temperatures between 150 and 300 Kelvin. This research is the combination of both water mechanics and two dimensional materials, two interesting but seemingly unrelated topics. Through hybrid research like this answers to problems we thought were impossible are often found.