In some heavy-ion reactions, such as ${}_{}{}^{24}{}_{}{}^{}\mathrm{Mg}$${(}^{16}$O${,}^{12}$C${)}^{28}$ Si oscillatory structure often appears in the whole angle region in the differential cross section. This anomalous phenomenon, unexpected from ordinary distorted-wave Born approximation theory, is explained by an alpha transfer process between two unidentical nuclear cores. Nuclear molecular-orbit theory has been formulated, and the coupled system of wave equations describing both the elastic scattering and transfer reaction channels are obtained. An independent α particle model is assumed in the evaluation of nuclear wave functions. The differential cross sections of both channels have been calculated simultaneously for two cases: ${}_{}{}^{24}{}_{}{}^{}\mathrm{Mg}$${(}^{16}$O${,}^{16}$O${)}^{24}$ Mg and ${}_{}{}^{24}{}_{}{}^{}\mathrm{Mg}$${(}^{16}$O${,}^{12}$C${)}^{28}$ Si as well as ${}_{}{}^{28}{}_{}{}^{}\mathrm{Si}$${(}^{16}$O${,}^{16}$O${)}^{28}$ Si and ${}_{}{}^{28}{}_{}{}^{}\mathrm{Si}$${(}^{16}$O${,}^{12}$C${)}^{32}$ S. Agreement with the experimental data can be reached in the whole angle region for both of these cases.

• Received 19 October 1984

DOI:https://doi.org/10.1103/PhysRevC.31.2128