research papers
The structure of nanocrystalline calcium silicate hydrates (C-S-H) was studied using X-ray diffraction and literature data. It is proposed that C-S-H of Ca/Si ratio ranging between ∼ 0.6 and ∼ 1.7 can be described as nanocrystalline tobermorite affected by turbostratic disorder. The broadening and shift of the basal reflection positioned between ∼ 13.5 and ∼ 11.2 Å (depending on the Ca/Si ratio) arises from nanocrystallinity and possibly from an interstratification phenomenon.