Where is theηc?

Incorporating asymptotic freedom into the simple Coulomb plus linear effective quark-antiquark potential, we predict the masses of the ${}_{}{}^1{}_{}{}^{}S_0^{}{}_{}{}^{}$ partners of $\frac{J}{\psi }$ and ${\psi }^{\prime }$, ${\eta }_c$ and ${\eta }_c^{\prime }$, to be $m_{{\eta }_c}\approx 3.01$ GeV and $m_{{\eta }_c^{\prime }}\approx 3.63$ GeV. Further implications of asymptotic freedom are considered, particularly the quark-mass dependence of the various level spacings.