Evolution of Strain in Heteroepitaxial Cadmium Carbonate Overgrowths on Dolomite

Journal Article · Mon Apr 09 00:00:00 EDT 2018 · Crystal Growth and Design

DOI:https://doi.org/10.1021/acs.cgd.7b01716· OSTI ID:1460956

La Plante, Erika Callagon ^[1]; Eng, Peter J. ^[2]; Lee, Sang Soo  ^[3]; Sturchio, Neil C. ^[4]; Nagy, Kathryn L. ^[1]; Fenter, Paul  ^[3]

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1. Univ. of Illinois, Chicago, IL (United States). Dept. of Earth and Environmental Sciences
2. Univ. of Chicago, IL (United States). Center for Advanced Radiation Sources (CARS)
3. Argonne National Lab. (ANL), Argonne, IL (United States). Chemical Sciences and Engineering Division
4. Univ. of Delaware, Newark, DE (United States). Dept. of Geological Sciences

The evolution and accommodation of lattice strain in an epitaxial mineral film grown on an isostructural substrate were observed as a function of film thickness. Cadmium carbonate films (approximately CdCO₃ (otavite) in composition) were grown on the (104) surface of CaMg(CO₃)₂ (dolomite) from aqueous solutions that were supersaturated with respect to both pure otavite and Cd-rich (Cd_1-xCa_x)CO₃. Specular and non-specular X-ray reflectivity (XR) revealed that the structure and strain of the otavite overgrowths evolved in a manner that is fully consistent with a Stranski-Krastanov growth mode. Otavite films initially grew as coherently strained films, up to an average thickness of ~15 Å, with lateral compressive strains and an expansion of the vertical film lattice spacing resulting in a unit cell volume consistent with pure otavite. Thicker films (>15 Å) became incommensurate with the substrate, having lattice parameters that are indistinguishable from pure otavite. These results indicate that the evolution of these mineral films is controlled by epitaxy and are consistent with the growth of essentially pure otavite films. Lastly, these results provide a foundation for understanding the stability of thin-film overgrowths in the natural environment.

• Research Organization: Argonne National Lab. (ANL), Argonne, IL (United States)
• Sponsoring Organization: USDOE Office of Science (SC), Basic Energy Sciences (BES)
• Grant/Contract Number: AC02-06CH11357
• OSTI ID: 1460956
• Journal Information: Crystal Growth and Design, Vol. 18, Issue 5; ISSN 1528-7483
• Publisher: American Chemical Society
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
Cadmium
calcium carbonate
calcite
dolomite
heteroepitaxial growth