The low-lying energy levels of ${\mathrm{O}}^{18}$ are calculated in the harmonic-oscillator shell model using as residual interaction the exponentially velocity-dependent singlet-even potential of Tabakin and Davies in combination with the triplet-odd potential of Green. The main result is that the energy levels so calculated agree closely with the energy levels of Kuo and Brown calculated without core polarization from the hard-core Hamada-Johnston nucleon-nucleon potential.

• Received 2 February 1968

DOI:https://doi.org/10.1103/PhysRev.170.879