中文摘要：

用全实加关联方法计算了类锂Cr^21＋离子1s^23d-1s^2nf（4≤n≤9）的跃迁能和1s^2nf（n≤9）态的精细结构．在类氢近似下估算了对能量的高阶相对论修正．依据量子亏损理论，确定了Rydberg系列1s^2nf的量子数亏损．据此可以实现对任意高激发态（n≥10）的能量的可靠预言．计算了Cr^21＋离子1s^23d-1s^2nf（4≤n≤9）跃迁的振子强度．与量子亏损理论相结合，得到该离子从1s^23d态到电离阈附近高激发束缚态间的偶极跃迁振子强度以及到相应连续态跃迁的振子强度密度，从而将Cr^21＋离子的这一重要光谱特性的理论预言外推到整个能域．

英文摘要：

The transition energy of 1s^23d - 1s^2nf（4≤ n≤9） and fine structure splitting of 1s^2nf（n≤9） states for lithium-like Cr^21 ＋ ion are calculated by using the full-core plus correlation method. The higher-order relativistic contribution to the energy is estimated under a hydrogenie approximation. The quantum defect of Rydberg series 1s^2nf is determined according to the quantum defect theory. The energies of any highly excited states with n≥10 for this series can be reliably predicted using the quantum defects which are function of energy. The dipole oscillator strengths for the 1s^23d- 1s^2nf（n≤9） transitions of Cr^21 ＋ ion are calculated with the energies and FCPC wave functions obtained above. Combining the quantum defect theory with the discrete oscillator strengths, the discrete oscillator strengths for the transitions from initial state 1s^23d to highly excited states 1s^2nf（n≥10） and the oscillator strengths density corresponding to the bound-free transitions are obtained.