1. ABOUT THE DATASET -------------------- Title: Dataset for "Magnesium Ions Direct the Solid-State Transformation of Amorphous Calcium Carbonate Thin Films to Aragonite, Magnesium-Calcite or Dolomite" Creator(s): Shuheng Zhang [1], Ouassef Nahi [1], Xuefeng He [1], Li Chen [2], Zabeada Aslam [3], Nikil Kapur [4], Yi-Yeoun Kim [1] and Fiona C. Meldrum [1] Organisation(s): 1. School of Chemistry, University of Leeds, Woodhouse Lane, Leeds LS2 9JT, UK 2. School of Electronic and Electrical Engineering, University of Leeds, Woodhouse Lane, Leeds LS2 9JT, UK 3. School of Chemical and Process Engineering, University of Leeds, Woodhouse Lane, Leeds LS2 9JT, UK 4. School of Mechanical Engineering, University of Leeds, Woodhouse Lane, Leeds LS2 9JT, UK Rights-holder(s): Copyright 2025 University of Leeds Publication Year:2025 Description: This dataset supports work showing that remarkable control can be achieved over the chemical composition and structure of crystalline calcium carbonate by using heat to drive a pseudomorphic transformation of ACC thin films. The crystal polymorph can be tuned from low magnesium-calcite to pure aragonite, high magnesium-calcite and ultimately dolomite according to the magnesium content of the ACC, and mosaics of large single crystals are generated at elevated temperatures rather than the spherulitic structures formed at room temperature. This methodology also enabled an in situ investigation of the ACC crystallization mechanism using Transmission Electron Microscopy. Finally, our approach can be combined with templating methods to generate arrays of large aragonite single crystals with pre-selected morphologies. These results demonstrate that exceptional control can be achieved through the solid-state transformation of Mg-ACC, which has relevance to both synthetic and biological systems. Cite as: Zhang, Nahi, He, Chen, Aslam, Kapur, Kim and Meldrum “Dataset for " Magnesium Ions Direct the Solid-State Transformation of Amorphous Calcium Carbonate Thin Films to Aragonite, Magnesium-Calcite or Dolomite” University of Leeds. [Dataset] https://doi.org/10.5518/1103 Related publication: Zhang S., Nahi O., He X., Chen L., Aslam Z., Kapur N., Kim Y-Y. and Meldrum F.C. “Magnesium Ions Direct the Solid-State Transformation of Amorphous Calcium Carbonate Thin Films to Aragonite, Magnesium-Calcite or Dolomite” Adv. Func. Mater. (2022) 32(25), 2201394. 2. TERMS OF USE --------------- Copyright [2025] [University of Leeds]. This dataset is licensed under a Creative Commons Attribution 4.0 International Licence: https://creativecommons.org/licenses/by/4.0/ 3. PROJECT AND FUNDING INFORMATION ---------------------------------- Title: DYNAMIN Dates: Sept 2018 to Aug 2025 Funding organisation: ERC Grant no.: Grant Agreement No. 788968 Title: Crystallisation in the Real World: Delivering Control through Theory and Experiment Dates: Mar 2018 - Feb 2024 Funding organisation: EPSRC Grant no.: EP/R018820/1 4. CONTENTS ----------- File: SEM-raw.zip images of the patterned ACC disc File: TEM.zip Raw data of Bright field TEM images and corresponding SAED patterns of samples described in the main article File: HAADF-STEM-EDX.zip Raw and processed STEM-EDX data that are listed in Table 1 File: Raman.zip Raman microscopy spectra of the ACC and aragonite films File: AFM_data.zip Raw AFM data of ACC and crystalline CaCO3 films File: OM_images.zip Optical micrographs of ACC and crystalline CaCO3 films Files: Individual Fig Files Data appearing in individual Figures in paper File: Supplementary Information SI as published with linked article 5. METHODS ---------- A full description of the methods and how data were recorded is provided in the associated full publication.