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Formation of the σ‐hole and the halogen bond interaction can also be described using atomic orbital theory. To paraphrase Clark, Murray, and Politzer, the electron‐deficient σ‐hole is caused by depleted occupancy in the outer lobe of a p‐orbital of a covalent bond [8]. The halogen “X” has an s²p_x²p_y²p_z¹ electronic configuration where the RX bond is on the z‐axis. In this electron configuration, two p‐orbitals are filled, and one is half filled, thus highlighting the depleted electron density in the p_z orbital. This picture becomes more relevant with larger halogens and is more exaggerated when the halogen is covalently bound to an electron‐withdrawing system. For example, this orbital character does not appear for fluorine. As fluorine is very electronegative, it shares more of the sigma bonding electrons, creating a higher degree of sp hybridization than larger halogens. Moving additional electron density into the p_z orbital affectively reduces the σ‐hole. For example, in a CF bond, 71.4% of electrons reside on F, whereas for less electronegative, larger halogens, like I, only ∼50% of the electron density resides on the halogen [8]. Meanwhile, the σ‐hole does not form for neutral, symmetric halogen containing molecules with equal electron distribution (e.g. carbon tetrahalides, hexahalobenzenes). This does not necessarily mean that symmetric or F‐based systems do not form halogen bonds; rather other attractive components become the dominate force.