Morphology of Calcite (CaCO3) Crystals Growing from Aqueous Solutions in the Presence of Li+ Ions. Surface Behavior of the {0001} Form

• Published in: Crystal growth & design Vol. 4; no. 3; pp. 485 - 490
• Main Authors: Pastero, Linda, Costa, Emanuele, Bruno, Marco, Rubbo, Marco, Sgualdino, Giulio, Aquilano, Dino
• Format: Journal Article
• Language: English
• Published: Washington,DC American Chemical Society 01.05.2004
• Subjects: Cross-disciplinary physics: materials science; rheology; Exact sciences and technology; Growth from solutions; Materials science; Methods of crystal growth; physics of crystal growth; Physics; Inorganic compounds; Adsorption; Trigonal lattices; Aqueous solutions; Supersaturated solution; Ternary compounds; Morphology; Crystal growth from solutions; Experimental study; Calcite; Surface structure
• ISSN: 1528-7483; 1528-7505
• DOI: 10.1021/cg034217r

Calcite crystals were nucleated and grown from supersaturated aqueous solutions in the presence of variable concentrations of lithium. The diagram of supersaturation vs [Li+]/[Ca2+] concentration ratio (“morphodrome”) shows a continuous habit variation, from the dominant {011̄1} rhombohedron (at low [Li+]/[Ca2+] ratio) to the dominant {0001} form (at high [Li+]/[Ca2+] ratio). The morphological change is interpreted in terms of two-dimensional layers having the structure of the monoclinic Li2CO3 crystal which are epitaxially adsorbed on the restructured {0001} form of calcite. Hence, even if {0001} is a K form (in the sense of Hartman-Perdok), the corresponding surface behaves like a F form, growing layer by layer from low to high supersaturation values.