sp3 Hybrids. The top four images show the four sp3 hybrids. These particular sp3 hybrids are combinations of 2s and three 2p functions. The bottom shows the relative positions of these four hybrids superimposed. Note that in each case, the nucleus is embedded in the minor lobe.
There are four sp3 hybrid orbitals. Each is the same as the other but one is rotated by 109.5° relative to the other. It is appropriate to invoke sp3 hybrid orbitals in molecules such as TiCl4 or CH4 where the Cl-Ti-Cl and H-C-H angles are 109.5°.