10.1021/jp302218j.s002
Pawel Rejmak
Pawel
Rejmak
Jorge S. Dolado
Jorge S.
Dolado
Malcolm
J. Stott
Malcolm
J.
Stott
Andrés Ayuela
Andrés
Ayuela
<sup>29</sup>Si NMR in
Cement: A Theoretical Study
on Calcium Silicate Hydrates
American Chemical Society
2012
29 Si
results show
29 Si chemical shifts
tobermorite minerals
Theoretical Study
29 Si NMR
silicon atoms
gel
Calcium Silicate HydratesThe NMR spectra
NMR spectra
model
2012-05-03 00:00:00
Journal contribution
https://acs.figshare.com/articles/journal_contribution/_sup_29_sup_Si_NMR_in_Cement_A_Theoretical_Study_on_Calcium_Silicate_Hydrates/2526259
The NMR spectra of <sup>29</sup>Si in cement-based materials
are
studied through calculations of the isotropic shielding of silicon
atoms within the density functional theory. We focus on the main component
of cement, the calcium-silicate-hydrate gel, using widely accepted
models based on the observed structures of jennite and tobermorite
minerals. The results show that the <sup>29</sup>Si chemical shifts
are dependent not only on the degree of condensation of the (SiO<sub>4</sub>) units, as commonly assumed, but also on the local arrangement
of the charge compensating H and Ca cations. We find that the NMR
spectra for models of the calcium-silicate-hydrate gel based on tobermorite
are in better agreement with experiment than those for jennite-based
models.