Abstract
A study of the photoionization of atomic Cr has been carried out based on the many-body perturbation theory. Total cross section was calculated near the 3p threshold. A well-developed Rydberg structure that never shows on the other members of iron group was found in the results. The effects of various diagrams included in the calculation were discussed. It shows that the interaction between the states 3p{sup 6}3d{sup 4}4s{sup 1}kf, 3p{sup 5}3d{sup 6}4s{sup 1}, and 3p{sup 5}3d{sup 5}4s{sup 1}nd is relatively significant compared with that in the other transition metal elements. It explains this abnormal behavior. The comparison with experimental results was also presented.