Small interference between wave-like

To improve our model still further, we have to visualize s- and p-orbitals as waves of electron density centered on the nucleus of an atom. Like waves in water, the four orbitals interfere with one another and produce new patterns where they intersect. These new patterns are called hybrid orbitals. The four hybrid orbitals are identical to one another except that they point toward different comers of a tetrahedron (Fig. 3.16). Each orbital has a node close to the nucleus and a small tail on the other side where the s- and p-orbitals do not completely cancel. These four hybrid orbitals are called sp3 hybrids because they are formed from one s-orbital and three p-orbitals. In an orbital-energy diagram, we represent the hybridization as the formation of four orbitals of equal energy intermediate between the energies of the s- and /7-orbitals from which they are constructed (43). The hybrids are colored green to remind us that they are a blend of (blue) s-orbitals and (yellow) p-orbitals. 

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