**Steric Reason for the Stability of SF6**

**Introduction**
Sulfur hexafluoride (SF6) is a highly stable compound consisting of one sulfur atom bonded to six fluorine atoms. It is widely used in various industrial applications due to its excellent electrical insulating properties. The stability of SF6 can be attributed to steric reasons, which are related to the arrangement of atoms around the central sulfur atom.

**Steric Effect**
The steric effect refers to the influence of spatial arrangement or size of substituents on the reactivity or stability of a molecule. In the case of SF6, the steric effect plays a crucial role in its stability.

**Steric Hindrance**
Steric hindrance occurs when bulky groups or atoms are present around a central atom, limiting the approach of other reactants or interfering with their interactions. In SF6, the six fluorine atoms surrounding the central sulfur atom create a significant steric hindrance due to their large size and electron density.

**Steric Repulsion**
The presence of six fluorine atoms in SF6 results in repulsive interactions between the electron clouds of adjacent fluorine atoms. This repulsion leads to the expansion of the electron cloud around the central sulfur atom, resulting in a larger molecular size. The repulsive interactions between the fluorine atoms help stabilize the SF6 molecule.

**Octahedral Geometry**
SF6 adopts an octahedral geometry, where the central sulfur atom is surrounded by six fluorine atoms arranged symmetrically. The octahedral geometry maximizes the distance between the fluorine atoms, reducing the steric repulsion and stabilizing the molecule.

**Steric Reason for Stability**
The steric reason for the stability of SF6 can be summarized as follows:

1. Steric hindrance caused by the bulky fluorine atoms limits the approach of potential reactants, reducing the likelihood of chemical reactions.
2. The steric repulsion between the fluorine atoms leads to the expansion of the electron cloud around the central sulfur atom, resulting in a larger molecular size and increased stability.
3. The octahedral geometry of SF6 minimizes the steric repulsion between the fluorine atoms, further stabilizing the molecule.

Overall, the steric hindrance and repulsion in SF6 contribute to its stability by preventing unwanted interactions and maintaining a balanced electron distribution.

SF6 is extremely stable for purely steric reason , because S is completely surrounded by flourine atoms from all directions , so the reaction starting with an attack on S that otherwise would readily occur(hydrolysis,etc) never have the chance to occur . This has nothing to do with electronegativity.