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Sulfur hexafluoride or sulphur hexafluoride (British spelling) is an inorganic compound with the formula SF 6.It is a colorless, odorless, non-flammable, and non-toxic gas.SF
Valence shell electron pair repulsion (VSEPR) theory (/ ˈ v ɛ s p ər, v ə ˈ s ɛ p ər / VESP-ər, [1]: 410 və-SEP-ər [2]) is a model used in chemistry to predict the geometry of individual molecules from the number of electron pairs surrounding their central atoms. [3]
Structure of iodine heptafluoride, an example of a molecule with the pentagonal-bipyramidal coordination geometry.. In chemistry, a pentagonal bipyramid is a molecular geometry with one atom at the centre with seven ligands at the corners of a pentagonal bipyramid.
If the ligand atoms were connected, the resulting shape would be that of a pyramid with a square base. The point group symmetry involved is of type C 4v. The geometry is common for certain main group compounds that have a stereochemically-active lone pair, as described by VSEPR theory.
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This geometry is almost always consistent with VSEPR theory, which usually explains non-collinearity of atoms with a presence of lone pairs. There are several variants of bending, where the most common is AX 2 E 2 where two covalent bonds and two lone pairs of the central atom (A) form a complete 8-electron shell .
This shape is found when there are four bonds all on one central atom, with no extra unshared electron pairs. In accordance with the VSEPR (valence-shell electron pair repulsion theory), the bond angles between the electron bonds are arccos(− 1 / 3 ) = 109.47°. For example, methane (CH 4) is a tetrahedral molecule.
For a free ion, e.g. gaseous Ni 2+ or Mo 0, the energy of the d-orbitals are equal in energy; that is, they are "degenerate". In an octahedral complex, this degeneracy is lifted. The energy of the d z 2 and d x 2 −y 2, the so-called e g set, which are aimed directly at the ligands are destabilized.