sp² Hybridization

C*: 1s², 2s¹, 2p_x¹, 2p_y¹, 2p_z¹

sp² Hybridization occurs when carbon is in its excited state (C*). In this case however, only two of the 2p-orbitals and the one 2s-orbital take part in the hybridization process.

This results in the formation of three equivalent sp²-hybrid orbitals, which adopt a trigonal planar geometry, and one unchanged p-orbital that lies at right angles to the plane of the hybrid orbitals.