molecular orbital

In chemistry, a molecular orbital is a region in which an electron may be found in a molecule. MOs are introduced in qualitative and pictorial models of bonding in molecules, and specify the spatial distribution and energy of one (or a pair) of electrons. More precisely, they are found quantitatively as wave functions, mathematical solutions to the Schrödinger wave equation for a molecule, using an approximation known as the Hartree-Fock or Self-Consistent Field method.
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Compare with atomic orbital and orbital .A wavefunction that describes the behavior of an electron in a molecule. Molecular orbitals are usually spread across many atoms in the molecule, and they are often described as a combination of atomic orbitals on those atoms.