Zou Zhaoyong, Habraken Wouter J E M, Matveeva Galina, Jensen Anders C S, Bertinetti Luca, Hood Matthew A, Sun Chang-Yu, Gilbert Pupa U P A, Polishchuk Iryna, Pokroy Boaz, Mahamid Julia, Politi Yael, Weiner Steve, Werner Peter, Bette Sebastian, Dinnebier Robert, Kolb Ute, Zolotoyabko Emil, Fratzl Peter
Department of Biomaterials, Max Planck Institute of Colloids and Interfaces, Potsdam, Germany.
Johannes Gutenberg-Universität Mainz, Institut für Anorganische und Analytische Chemie, Mainz, Germany.
Science. 2019 Jan 25;363(6425):396-400. doi: 10.1126/science.aav0210.
As one of the most abundant materials in the world, calcium carbonate, CaCO, is the main constituent of the skeletons and shells of various marine organisms. It is used in the cement industry and plays a crucial role in the global carbon cycle and formation of sedimentary rocks. For more than a century, only three polymorphs of pure CaCO-calcite, aragonite, and vaterite-were known to exist at ambient conditions, as well as two hydrated crystal phases, monohydrocalcite (CaCO·1HO) and ikaite (CaCO·6HO). While investigating the role of magnesium ions in crystallization pathways of amorphous calcium carbonate, we unexpectedly discovered an unknown crystalline phase, hemihydrate CaCO·½HO, with monoclinic structure. This discovery may have important implications in biomineralization, geology, and industrial processes based on hydration of CaCO.
作为世界上储量最为丰富的物质之一，碳酸钙（CaCO₃）是各种海洋生物骨骼和外壳的主要成分。它被用于水泥工业，在全球碳循环和沉积岩形成过程中发挥着关键作用。一个多世纪以来，在环境条件下，人们只知道纯碳酸钙有三种多晶型物——方解石、文石和球霰石，以及两种水合晶相——一水碳酸钙（CaCO₃·1H₂O）和六水碳酸钙（CaCO₃·6H₂O）。在研究镁离子在无定形碳酸钙结晶途径中的作用时，我们意外地发现了一种未知的晶相——半水碳酸钙（CaCO₃·½H₂O），其具有单斜结构。这一发现可能对生物矿化、地质学以及基于碳酸钙水合作用的工业过程具有重要意义。
