Print Email Facebook Twitter A molecular dynamics study of N–A–S–H gel with various Si/Al ratios Title A molecular dynamics study of N–A–S–H gel with various Si/Al ratios Author Chen, Y. (TU Delft Materials and Environment; South China University of Technology) Dolado, Jorge S. (Centro Mixto CSIC-UPV/EHU; Donostia International Physics Center) Li, Z. (TU Delft Materials and Environment) Yin, Suhong (South China University of Technology) Yu, Qijun (South China University of Technology) Kostiuchenko, A. (TU Delft Materials and Environment) Ye, G. (TU Delft Materials and Environment; Universiteit Gent) Date 2022 Abstract In this paper, the atomic structures of sodium aluminosilicate hydrate (N–A–S–H) gels with different Si/Al ratios are studied by molecular dynamics simulation. An N–A–S–H gel model was obtained from the polymerization of Si(OH)4 and Al(OH)3 monomers with the use of a reactive force field (ReaxFF). The simulated atomic structural features, such as the bond length, bond angle, and simulated X-ray diffraction pattern of the gel structure are in good accordance with the experimental results in the literature. Si–O–Al is found to be preferred over Si–O–Si in the N–A–S–H gel structure according to the amount of T–O–T bond angles and distribution of Si4(mAl). Pentacoordinate Al is identified in all simulated N–A–S–H models. It provides strong support to current knowledge that pentacoordinate Al in geopolymer does not only come from raw material. Furthermore, the structural analysis results also show that N–A–S–H gel with lower Si/Al ratios has a more cross-linked and compacted structure. Subject atomic structuresmolecular dynamicsN–A–S–H gelReaxFFSi/Al ratio To reference this document use: http://resolver.tudelft.nl/uuid:84498de7-5934-4325-895b-a1ce144f2d44 DOI https://doi.org/10.1111/jace.18597 ISSN 0002-7820 Source Journal of the American Ceramic Society, 105 (10), 6462-6474 Part of collection Institutional Repository Document type journal article Rights © 2022 Y. Chen, Jorge S. Dolado, Z. Li, Suhong Yin, Qijun Yu, A. Kostiuchenko, G. Ye Files PDF Journal_of_the_American_C ... ratios.pdf 3.67 MB Close viewer /islandora/object/uuid:84498de7-5934-4325-895b-a1ce144f2d44/datastream/OBJ/view