Polymorphism of tricalcium silicate, the major compound of Portland cement clinker: 1. Structural data: review and unified analysis

This paper reviews the literature devoted to structural investigations, with a special concern to the various notations used by different authors. A unified analysis of the known T1, M1, M3 and R polymorphs is proposed. The superstructure relations between the various unit cells are discussed, together with the evidence of common 1D and 2D structural elements in all these polymorphs. These structural elements are related to the observed properties.