Tricalcium Silicate T₁ and T₂ Polymorphic Investigations: Rietveld Refinement at Various Temperatures Using Synchrotron Powder Diffraction

Abstract

The lattice parameters, cell volume, and structure of a sample of phase pure triclinic tricalcium silicate were determined using in situ, high‐temperature synchrotron powder diffraction and full‐profile Rietveld refinement. The temperature range covered was from ambient to 740°C. Evidence of superstructure was found. The T2 type structure with disordered SiO4 tetrahedra was observed, and an average structure for the subcell (P, a= 11.7416(2) Å, b= 14.2785(2) Å, c= 13.7732(2) Å, α= 105.129(1)°, β= 94.415(1)°, and γ= 89.889(1)°) is presented. Differential thermal analysis and X‐ray fluorescence was also performed.

Fundamental principles that govern the copper doping behavior in complex clinker system

“…Tricalcium silicate (Ca 3 SiO 5 , C 3 S), dicalcium silicate (Ca 2 SiO 4 , C 2 S), tricalcium aluminate (Ca 3 Al 2 O 6 , C 3 A), and tetracalcium aluminoferrite (Ca 2 AlFeO 5 , C 4 AF) are the 4 dominant mineral phases of OPC clinker. C 3 S, known as alite, is the predominant phase in OPC clinker, which has 7 polymorphs including orthorhombic (R), monoclinic (M3, M2, M1), and triclinic (T3, T2, T1) forms . The T1‐C 3 S form (space group: P ‐1) with its primitive cell having 162 atoms is chosen for our study because it is the only stable form at room temperature without impurity incorporation .…”

Research review of cement clinker chemistry

“…Only three polymorphic structures (R, M3 and T1) of C 3 S have been determined by synthesizing single crystals [2][3][4][5]. In order to perform accurate Rietveld quantitative phase analysis (QXRD), several studies in the last decade have focused on the crystal structure of alite [6][7][8][9][10]. Various models are available for T1, T2, T3, M1, M3 and R polymorphs, however, there is still no structural model for the M2 polymorph.…”

Low Temperature Synthesis of Belite Cement Based on Silica Fume and Lime

“…Reactivity and hydraulic properties of stabilized β -C 2 S depend on the type and amount of the stabilizing ions [13]. On the other hand, fast cooling may produce fine β -C 2 S crystals affording β - γ -C 2 S transformation, even without the need for stabilizer [14]. Based on density functional theory calculations, stabilizing ions modify charge density localization of the electronic structure of C 2 S and enhance the reactivity and in turn would broaden the applicability of C 2 S [7].…”