CH7001 — Environmental Impact of Energy Utilisation
Continuous assessment
In the same folder where you can download this continuous assessment handout, you will find and download the crystal index files (CIF) for six carbonate minerals: calcite, monohydrocalcite, vaterite, aragonite, ikaite, and CCH (calcium carbonate hemihydrate).
These minerals are by-products of carbonation reactions, and some of them can form. during the course of carbon capture and storage processes. You are required to use the visualization and analysis software VESTA to explore the crystal structures of these minerals.
Question 1: Structural Analysis of Carbonate Minerals
Using VESTA, perform. a detailed structural analysis of the carbonate minerals provided. In your response, include the following aspects:
• Composition: Identify the chemical formula of each mineral and its constituent elements.
• Coordination polyhedra: Describe the types of coordination polyhedra (e.g., tetrahedra, octahedra) surrounding the central atoms, specifically focusing on the cations and their coordination with surrounding anions.
• Arrangement of polyhedra: Explain how the coordination polyhedra are interconnected or arranged within the mineral structure. Are they isolated, sharing corners, edges, or faces?
• Other structural features: Highlight any significant structural features such as layers, chains, or frameworks, or specific bonds that are evident.
Question 2: Mineral Stability Based on Structure
Based on the structural analysis conducted in Question 1, discuss the potential stability of each mineral under different environmental conditions (e.g., temperature, pressure, chemical environment). Consider the following:
• Bond Strength: How do the bond types and coordination environments influence the mineral's stability?
• Structural Features: Does the arrangement of the coordination polyhedra suggest any inherent strengths or weaknesses in the mineral's structure? For instance, are there any indications of structural robustness or susceptibility to chemical breakdown or alteration?
Be sure to justify your conclusions with reference to the specific mineral structures you examined in VESTA.
VESTA download page: https://jp-minerals.org/vesta/en/download.html