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Supersaturated calcium carbonate solutions are classical.

ABSTRACT: Mechanisms of CaCO3 nucleation from solutions that depend on multistage pathways and the existence of species far more complex than simple ions or ion pairs have recently been proposed. Herein, we provide a tightly coupled theoretical and experimental study on the pathways that precede the initial stages of CaCO3 nucleation. Starting from molecular simulations, we succeed in correctly predicting bulk thermodynamic quantities and experimental data, including equilibrium constants, titration curves, and detailed x-ray absorption spectra taken from the supersaturated CaCO3 solutions. The picture that emerges is in complete agreement with classical views of cluster populations in which ions and ion pairs dominate, with the concomitant free energy landscapes following classical nucleation theory.

SUBMITTER: Henzler K

PROVIDER: S-EPMC5786440 | biostudies-literature | 2018 Jan

REPOSITORIES: biostudies-literature

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Supersaturated calcium carbonate solutions are classical.

Henzler Katja K Fetisov Evgenii O EO Galib Mirza M Galib Mirza M Baer Marcel D MD Legg Benjamin A BA Borca Camelia C Xto Jacinta M JM Pin Sonia S Fulton John L JL Schenter Gregory K GK Govind Niranjan N Siepmann J Ilja JI Mundy Christopher J CJ Huthwelker Thomas T De Yoreo James J JJ

Science advances 20180126 1

Mechanisms of CaCO<sub>3</sub> nucleation from solutions that depend on multistage pathways and the existence of species far more complex than simple ions or ion pairs have recently been proposed. Herein, we provide a tightly coupled theoretical and experimental study on the pathways that precede the initial stages of CaCO<sub>3</sub> nucleation. Starting from molecular simulations, we succeed in correctly predicting bulk thermodynamic quantities and experimental data, including equilibrium cons ...[more]

PMID: 29387793

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