Comment on ‘‘Suppressed electron capture in slow ${\mathrm{O}}^{+}$${(}^4$${\mathit{S}}^{\mathit{o}}$${,}^2$${\mathit{D}}^{\mathit{o}}$${,}^2$${\mathit{P}}^{\mathit{o}}$)-He collisions’’

Electron capture in collisions of ${\mathrm{O}}^{+}$ ions with He atoms is studied on the basis of a molecular-orbital expansion approach. The cross section for electron capture by metastable ${\mathrm{O}}^{+}$ ${(}^2$D, ${}_{}{}^2{}_{}{}^{}$P) ions is found to be larger by an order of magnitude than that for capture by ground-state ${\mathrm{O}}^{+}$ ${(}^4$S) ions over the entire energy region studied. The energy dependencies of cross sections for electron capture by the ground and metastable ions are found to differ considerably below 2 keV. The present result, obtained by combining the cross section of 90% of the ground state and that of 10% of metastable states, reproduces reasonably well the experimental result of Kusakabe et al. [J. Phys. Soc. Jpn. 59, 1987 (1990)], who reported using the mixture of the ground and metastable ${\mathrm{O}}^{+}$ ions. The present finding clearly contradicts another experimental result of Wolfrum et al. [Phys. Rev. A 45, R4218 (1992)], who reported no effect from the metastable states.