Advanced Topic 713 of 1102 Inorganic Chemistry
Solid State Inorganic Structures
Perovskite, spinel and rock salt are common arrangements of ions in inorganic solids.
In-depth explanation of Solid State Inorganic Structures
Many inorganic solids adopt common structure types in which large anions form close-packed arrays and smaller cations occupy the holes. In rock salt, NaCl, each ion is octahedrally surrounded by six ions of the opposite charge. In fluorite, CaF2, calcium is coordinated by eight fluorides, while in zinc blende, ZnS, zinc is tetrahedrally coordinated. Spinel, AB2O4, and perovskite, ABX3, are important oxide structures with mixed cation sites. The ratio of cation to anion radius, together with charge balance, determines which structure is adopted.
Going deeper: Solid State Inorganic Structures
Key ideas: Close packing gives 74 percent filling with hcp (ABAB) and ccp or fcc (ABCABC), with coordination number 12. Per fcc cell 4 atoms, 4 octahedral and 8 tetrahedral holes. Radius ratio sets coordination: 0.414 to 0.732 octahedral (NaCl), 0.225 to 0.414 tetrahedral (ZnS), above 0.732 cubic (CsCl). Rock salt has 4 formula units per cell, fluorite CaF2 has 4 with Ca in fcc, spinel AB2O4 has A in tetrahedral holes and B in octahedral.
Common mistakes and connections: Students count atoms per cell incorrectly: corners count 1/8, faces 1/2, edges 1/4. Radius ratio is a guide, not a rule, as covalent character and polarization matter. Density: d = Z M over N_A a^3. Links to crystal field theory (site preferences), perovskites, defects and lattice energy.
Visualization of Solid State Inorganic Structures
Face-centred cubic lattice, the cubic close-packed arrangement with a coordination number of 12 found in many metals and ionic solids. The interactive lesson shows this as a live animation or chart.
Worked example and use case
Magnesium aluminate, MgAl2O4, is the mineral spinel, which has a cubic close-packed oxide lattice.
Frequently asked questions about Solid State Inorganic Structures
What is Solid State Inorganic Structures?
Perovskite, spinel and rock salt are common arrangements of ions in inorganic solids.
Is Solid State Inorganic Structures a beginner, intermediate or advanced topic?
Solid State Inorganic Structures is a advanced topic in Inorganic Chemistry. It builds on beginner and intermediate topics, so review those first if needed.
What should I learn before Solid State Inorganic Structures?
Study these earlier topics in Inorganic Chemistry first: Superconductors, Zintl Phases, Cluster Compounds.
What comes after Solid State Inorganic Structures?
The next topics in Inorganic Chemistry are Perovskites and Metal-Organic Frameworks.
Can I practise Solid State Inorganic Structures with quizzes?
Yes. The interactive lesson includes a self-check question on Solid State Inorganic Structures, and the Inorganic Chemistry quiz draws on every topic in this area.
Where Solid State Inorganic Structures fits in Inorganic Chemistry
Solid State Inorganic Structures is topic 98 of 113 in Inorganic Chemistry.