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In page Atomic orbital:

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Below is a list of these Cartesian polynomial names for the atomic orbitals.[7][8] There does not seem to be reference in the literature as to how to abbreviate the long Cartesian spherical harmonic polynomials for > 3 {\displaystyle \ell >3} so there does not seem be consensus on the naming of g {\displaystyle g} orbitals or higher according to this nomenclature.[citation needed]