# What is the geometrical structure of OF₂?

Is it linear, angular, triangular or tetragonal? Well, since $\ce{O}$ has 2 electron matches of his own, I think it's tetragonal, but in wikipedia it is angular... Why? What about $\ce{CS2}$, is it linear?

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Oxygen difluoride ($\ce{OF2}$) is analogous to water ($\ce{OH2}$) both in terms of structure and hybridization.

$\ce{OF2}$ has 4 ligands around the central oxygen, 2 $\ce{O-F}$ bonds and 2 lone pairs. Just like in water these 4 ligands assume a roughly tetrahedral geometry around the central oxygen. Again like in water, the $\ce{F-O-F}$ angle is less than the perfect tetrahedral angle (109.5°), in this case being around 103°.

Carbon disulphide ($\ce{CS2}$) is linear. It is analogous to the 3 carbons in allene, in both compounds the central carbon is $\ce{sp}$ hybridized making the $\ce{X=C=X}$ structure linear.

You're right, if you're talking about the arrangement which take the nonbonding electrons into consideration, Which is not the case in VSEPR geometry, Since we have a difference in electronegativity between F and O (F is more electronegative) , so we will have AX2 geometry which is angular.

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The angular structure is actually a distortion produced by the bond pair electrons (between oxygen and fluorine) and lone pair electrons of oxygen since every structure tries to decrease its net potential energy they assume this shape. This doesn't happen in case of Carbon-disulphide because the sulphur atoms each make a double bond with carbon leaving no lone pair or relative high electron density on carbon atom, instead the two sulphur atoms with 2 lone airs each after forming double bonds, repel each other into a configuration of linear to minimise their relative potential energies.