We present a complex-coordinate rotation calculation for doubly excited ${}_{}{}^{1,3}{}_{}{}^{}$${\mathit{D}}^{\mathit{o}}$ and ${}_{}{}^1{}_{}{}^{}$${\mathit{D}}^{\mathit{e}}$ resonance states in ${\mathrm{H}}^{\mathrm{-}}$ associated with the N=3 threshold of hydrogen atoms. Elaborate Hylleraas-type wave functions with up to M=1330 terms for ${}_{}{}^{1,3}{}_{}{}^{}$${\mathit{D}}^{\mathit{o}}$ states and M=1430 terms for ${}_{}{}^1{}_{}{}^{}$${\mathit{D}}^{\mathit{e}}$ states are used. In addition to ${}_{}{}^{1,3}{}_{}{}^{}$${\mathit{D}}^{\mathit{o}}$ and ${}_{}{}^1{}_{}{}^{}$${\mathit{D}}^{\mathit{e}}$ Feshbach resonances, we have identified a ${}_{}{}^3{}_{}{}^{}$${\mathit{D}}^{\mathit{o}}$ shape resonance lying above the H(N=3) threshold. With the present results for the D-wave resonances, together with the other angular-momentum states determined in earlier complex-rotation calculations, all the doubly excited intrashell states of ${\mathrm{H}}^{\mathrm{-}}$ associated with the hydrogen N=3 threshold are now accounted for.

• Received 13 May 1994

DOI:https://doi.org/10.1103/PhysRevA.50.4886