An sp3 hybrid orbital is an orbital formed by the linear combination of one s and three p orbitals of comparable energy (such 2s and 2p orbitals) on a same atom. The four sp3 hybrid orbitals point toward the corners of a regular tetrahedron with the bond angle of 109.5°.
Generalic, Eni. "Sp3 hybrid orbital." Croatian-English Chemistry Dictionary & Glossary. 29 June 2022. KTF-Split. {Date of access}. <https://glossary.periodni.com>.
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