Out-of-phase (destructive) overlap is the combination of atomic orbitals of opposite sign, which decreases the electron density between the nuclei and creates a node there. The lack of electron density between the nuclei raises the energy, producing an antibonding molecular orbital. It contrasts with in-phase overlap, which produces a bonding orbital.

反相(相消)重叠是符号相反的原子轨道组合,它使两核之间的电子密度减小并在该处形成节面。两核间电子密度的缺乏使能量升高,形成反键分子轨道。它与产生成键轨道的同相重叠相对。