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Inverse spinel structures have a different cation distribution in that all of the A cations and half of the B cations occupy octahedral sites, while the other half of the B cations occupy tetrahedral sites. An example of an inverse spinel is Fe 3 O 4, if the Fe 2+ (A 2+) ions are d 6 high-spin and the Fe 3+ (B 3+) ions are d 5 high-spin.
Polyhedral representation of spinel MgAl 2 O 4. Spinel (/ s p ɪ ˈ n ɛ l, ˈ s p ɪ n əl / [7]) is the magnesium/aluminium member of the larger spinel group of minerals. It has the formula MgAl 2 O 4 in the cubic crystal system. Its name comes from the Latin word spinella, a diminutive form of spine, in reference to its pointed crystals. [5]
Pages in category "Spinel group" The following 19 pages are in this category, out of 19 total. This list may not reflect recent changes. ...
The mineral ceylonite has the chemical composition of (Mg, Fe 2+) Al 2 O 4, putting it into a group of minerals known as the spinel group, or the oxide spinels. The oxide spinels have a formula of the model [A][B] 2 O 4; where [A] is commonly Fe 2+, Mg 2+, or Mn 2+, and [B] is Fe 3+, Al 3+, or Cr 3+. It is an iron-rich variety of the spinel ...
A chemical element, often simply called an element, is a type of atom which has a specific number of protons in its atomic nucleus (i.e., a specific atomic number, or Z). [ 1 ] The definitive visualisation of all 118 elements is the periodic table of the elements , whose history along the principles of the periodic law was one of the founding ...
Cuprospinel, like many other spinels has the general formula AB 2 O 4.Yet, cuprospinel is an inverse spinel in that its A element, in this case copper (Cu 2+), only occupies octahedral sites in the structure and the B element, iron (Fe 2+ and Fe 3+), is split between the octahedral and tetrahedral sites in the structure.
It features three elements: Li, Nb, and O. Letting A and B represent cations and X an anion, these ternary groupings are organized by stoichiometric types A 2 BX 4, ABX 4, and ABX 3. A ternary compound of type A 2 BX 4 may be in the class of olivine, the spinel group, or phenakite. Examples include K 2 NiF 4, β-K 2 SO 4, and CaFe 2 O 4.
In geology and mineralogy, a mineral group is a set of mineral species with essentially the same crystal structure and composed of chemically similar elements. [1] Silicon-oxygen double chain in the anions of amphibole minerals. For example, the amphibole group consists of 15 or more mineral species, most of them with the general unit formula A ...