2.4: Bonding in Unsymmetrical Systems

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What about unsymmetrical systems, in which the two atoms are not identical? Again, the coefficients C₁ and C₂ will change. Consider CH₃F:

Screen Shot 2021-05-20 at 8.50.53 AM.png

Since F is the electronegative, the bonds are polarized (unequal). Thus, F likes having a higher electron density around it, so the \(σ\) bond is skewed and no longer symmetrical. By analogy, the exact opposite is true for the \(σ^{*}\).

Let’s return to betulin for a moment. Take a minute to look at its structure and think about how complex it would be if we drew molecular orbitals for every bond. That’s why we draw molecules using line-angle notation, a short-hand of the Lewis model of bonding. You just need to recognize where it comes from.

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