Nonorthogonality Effects in Successive Particle-Transfer Reactions

It is demonstrated that nonorthogonality effects can play a very important role in multistep processes involving successive particle-transfer reactions. This is shown for the particular example of the $({}_{}{}^3{}_{}{}^{}\mathrm{He}, d)-(d, t)$ process, where nonorthogonality terms can be included as a renormalization of the effective interaction for the direct (${}_{}{}^3{}_{}{}^{}\mathrm{He}$ $t$) charge-exchange process.