0000000000301155

AUTHOR

Yael Politi

showing 2 related works from this author

Differences between Bond Lengths in Biogenic and Geological Calcite

2010

8 pages; International audience; We used high-resolution neutron powder diffraction to accurately measure the atomic positions and bond lengths in biogenic and geological calcite. A special procedure for data analysis was developed in order to take into account the considerable amounts of magnesium present in all the investigated samples. As a result, in biogenic calcite we found some atomic bonds to have significantly different lengths as compared to those in geological calcite, after the contribution of magnesium is accounted for. The maximum effect (elongation up to 0.7%) was found for the C−O bonds. We also analyzed changes in frequencies and spectral widths of normal vibrations of carb…

Neutron diffractionMineralogychemistry.chemical_element02 engineering and technology010402 general chemistry01 natural scienceschemistry.chemical_compoundsymbols.namesake[ CHIM.CRIS ] Chemical Sciences/Cristallography[CHIM.CRIS]Chemical Sciences/CristallographyGeneral Materials Science[SDV.IB.BIO]Life Sciences [q-bio]/Bioengineering/BiomaterialsCalciteMagnesiumGeneral Chemistry[ SDV.IB.BIO ] Life Sciences [q-bio]/Bioengineering/Biomaterials021001 nanoscience & nanotechnologyCondensed Matter Physics0104 chemical sciencesBond lengthCalcium carbonatechemistrysymbolsCarbonate0210 nano-technologyRaman spectroscopyDoppler broadeningCrystal Growth & Design
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A hydrated crystalline calcium carbonate phase: Calcium carbonate hemihydrate.

2019

Hydrous CaCO 3 gets a new structure Calcium carbonate (CaCO 3 ) forms important minerals on Earth and is a model system for understanding crystal nucleation. Three different structures of CaCO 3 are known, along with two structures that are hydrated. Zou et al. found a third hydrated CaCO 3 structure formed from amorphous CaCO 3 in the presence of magnesium ions. The discovery illustrates the importance of amorphous precursors for producing new materials. Science , this issue p. 396

MultidisciplinaryGeneral Science & TechnologyAragoniteengineering.materialAmorphous calcium carbonateMonohydrocalcitelaw.inventionchemistry.chemical_compoundIkaiteCalcium carbonatechemistryChemical engineeringlawengineeringCrystallizationMagnesium ionBiomineralizationScience (New York, N.Y.)
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