Hybrid theory is a modification of atomic orbital theory that was developed to explain the shapes of molecules. For example, a tetrahedron cannot be formed if the only possible overlap of atoms is between s, p or d orbitals, so we picture bonding orbitals in a tetrahedral molecule as hybrids of s and p atomic orbitals that are oriented so they correspond to molecular shapes.


Suggested activity #1:

Since hybrid theory is so closely related to molecular shape, this database can be used as practice of determining the types of hybrids involved in various molecules. The "entry level" database would probably be most useful since the molecular shape is clearer, but it could also be interesting to try to predict what type of hybrids are found around each atom of a some of the more complex structures. The different versions of the databases will help regulate the complexity of the molecules being looked at. For example, the entry level database will only deal with hybrids of s and p orbitals, while the expanded valence database will keep the molecules fairly simple but will include hybrids consisting of s, p and d orbitals.



Suggested activity #2:

          Hybrid orbitals possess a combination of the characteristics of the component orbitals. For instance, an sp orbital possesses half s character and half p character. A sp2 hybrid has one third s character and two thirds p character. This idea can be conveyed by looking at the relative lengths of various hybrid orbitals. We suggest recording the bond lengths of a few sp, sp2 and sp3 molecules in a table to illustrate this phenomenon. Since a p orbital is longer than an s orbital, the more p character in the hybrid, the longer the bonds should be. (caution: compare molecules that are bonded to the same type of orbital in the other atom. For instance, compare