Читать книгу Foundations of Chemistry - Philippa B. Cranwell - Страница 97

The first stage in working out the shape of a molecule is to determine the number of areas of electron density around the central atom. This can be done by drawing a dot‐and‐cross diagram that shows the number of bonded electrons and the number of lone pairs. The number of areas of electron density is equal to the number of bonded atoms plus the number of lone pairs.

Once we know the number of areas of electron density, there are various fundamental shapes that the molecule can have that minimise the repulsive forces between these negatively charged areas.

In the following section, examples of molecules adopting these fundamental shapes are given so you can see how the overall shape is obtained.