An example-FeS2 J.Am.Chem.Soc.134,13216(2012 3 9 10 11 9 10 11 Atomic structures of FeS1.812500.187s alloys in a Atomic structures of FeS1.7500.2s alloys in a 2x2x2 supercell. 2x2×2 supercell.An example – FeS2 Atomic structures of FeS1.8125O0.1875 alloys in a 2×2×2 supercell. J. Am. Chem. Soc. 134, 13216 (2012) Atomic structures of FeS1.75O0.25 alloys in a 2×2×2 supercell