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The Atomic-Level Structure of Cementitious Calcium Aluminate Silicate Hydrate Determined by NMR
- Source :
- CHIMIA, Vol 75, Iss 4, Pp 272-275 (2021)
- Publication Year :
- 2021
- Publisher :
- Swiss Chemical Society, 2021.
-
Abstract
- We review our recent paper which resolves the long-standing dilemma of the location and nature of the six-fold coordinated aluminum in calcium aluminate silicate hydrate (C-A-S-H) samples. First principles calculations predict that at high Ca:Si and H2O ratios, aluminum is incorporated into the bridging sites of the linear silicate chains and that the stable coordination number is six. We confirm this hypothesis experimentally by one- and two-dimensional dynamic nuclear polarization enhanced 27 Al and 29 Si solid-state NMR experiments in which we correlate the distinctive six-fold coordinated aluminum NMR signal at 5 ppm to 29 Si NMR signals from silicates in C-A-S-H.
- Subjects :
- c-a-s-h
dnp.mas
six-fold coordinated alumnium
solid-state nmr
Chemistry
QD1-999
Subjects
Details
- Language :
- German, English, French
- ISSN :
- 00094293 and 26732424
- Volume :
- 75
- Issue :
- 4
- Database :
- Directory of Open Access Journals
- Journal :
- CHIMIA
- Publication Type :
- Academic Journal
- Accession number :
- edsdoj.42d75eeafd084333a1ac3ddc7fdbd980
- Document Type :
- article
- Full Text :
- https://doi.org/10.2533/chimia.2021.272