Steric Number in VSEPR
Calculating the steric number of a molecule's central atom is a vital step in predicting its geometry by VSEPR theory. On the molecule SF4, for example, the central sulfur atom has four ligands about it, calculated by considering sulfur's coordination number. In addition to the four ligands, sulfur also has one remaining lone pair (expanded octet does not apply in this compound). Thus, the steric number is 5. The central atom's steric number together with the number of lone pairs allows one to predict the geometry of that central atom, using the table of molecular geometries for the VSEPR theory.
Read more about this topic: Steric Number
Famous quotes containing the word number:
“No Government can be long secure without a formidable Opposition. It reduces their supporters to that tractable number which can be managed by the joint influences of fruition and hope. It offers vengeance to the discontented, and distinction to the ambitious; and employs the energies of aspiring spirits, who otherwise may prove traitors in a division or assassins in a debate.”
—Benjamin Disraeli (1804–1881)