Radiative corrections of the order $\alpha (Z\alpha {)}^6$ for rotational states of two-body systems

The analytical calculation of the complete $\alpha (Z\alpha {)}^6$ one-loop radiative correction to energies of two-body systems with the angular momenta $l>0$, consisting of a pointlike particle and an extended-size nucleus with arbitrary masses and spin 1/2, is presented. The obtained results apply to a wide variety of two-body systems, such as hydrogen, muonium, positronium, and antiprotonic atoms.