This model demonstrates the process of hybridization of atomic orbitals. If a chemical bond is established between two atoms, the form of the atomic orbitals may change. Consider the properties of s- and p-orbitals of atoms of p-elements that belong to the second period, on the example of a carbon atom. Excitement and transfer of one 2s-electron to vacant 2p-orbital precedes the formation of a carbon chemical bond. All four orbitals become equivalent in respect to their occupation with the electrons, but they remain non-equivalent in terms of energy. |
Hybridization is the conversion of s- and p-orbitals that have different symmetry and energy characteristics into orbitals that are equivalent in terms of symmetry and energy, but are not equivalent in respect to their spatial characteristics. Combining the spherically symmetrical 2s-orbital with dumbbell-like 2p-orbitals gives two, three or four hybrid atomic orbitals that are shaped like asymmetrical dumbbells. Configurations of hybrid orbitals are somewhat dependent on whether 1, 2 or 3 p-orbitals are involved in hybridization with one s-orbital (resulting respectively in sp -, sp2-, or sp3 - hybridization). The relative position of the hybrid orbitals strongly depends on the type of hybridization. Switch to "sp-hybridization" mode, and press Start. Note that the two newly formed hybrid orbitals are linear in shape. This causes the molecules wherein the hybridization occurs to assume a linear shape as well. (Here, we refer to molecules with triple bonds between carbon atoms, such as an acetylene molecule. See the "Multiple Bonds" model).
Switch to sp2 - hybridization mode. The three new hybrid orbitals are located on the same plane. They rotate at an angle of 120 degrees, causing the molecules with a double bond wherein the hybridization occurs to assume a "flat" structure. (An acetylene molecule is a good example - see "Multiple Bonds" model). Finally, in sp3 - hybridization mode, observe how the newly formed hybrid orbitals are directed towards the vertices of a tetrahedron, whose center coincides with the nucleus of a carbon atom. The molecule of methane has the shape of a tetrahedron, with hydrogen atoms located at its vertices, and a carbon atom located at its center.