General calculation of 4f-5d transition rates for rare-earth ions using many-body perturbation theory.
General calculation of 4f-5d transition rates for rare-earth ions using many-body perturbation theory.
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DOI：
10.1063/1.1855880
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发表时间：
2005-03
期刊：
影响因子：
--
通讯作者：
C. Duan;M. F. Reid
中科院分区：
文献类型：
--
作者：
C. Duan;M. F. Reid
用半经验晶体哈密顿量等有效哈密顿量计算4f（N）和4f（N-1）5d态之间的有效跃迁算符，可以计算晶体中稀土离子的4f-5d跃迁速率。有效跃迁算符与原始跃迁算符的差别是由于中心离子和配体离子的激发组态的跃迁初态和末态的混合而引起的修正。这些修正是用多体微扰理论计算的。对于自由离子，有重要的单体和两体修正。单体校正与原始电偶极子算子成比例，其幅度约为未校正电偶极矩的40%。其效果相当于将径向积分（5d/r/4f）按比例缩小到未校正HF值的约60%。相对于未校正的电偶极矩，两体校正具有约25%的量值。对于晶体中的离子，有一个额外的单体校正由于配体极化，其幅度被证明是约10%的未校正的电偶极矩。
The 4f-5d transition rates for rare-earth ions in crystals can be calculated with an effective transition operator acting between model 4f(N) and 4f(N-1)5d states calculated with effective Hamiltonian, such as semiempirical crystal Hamiltonian. The difference of the effective transition operator from the original transition operator is the corrections due to mixing in transition initial and final states of excited configurations from both the center ion and the ligand ions. These corrections are calculated using many-body perturbation theory. For free ions, there are important one-body and two-body corrections. The one-body correction is proportional to the original electric dipole operator with magnitude of approximately 40% of the uncorrected electric dipole moment. Its effect is equivalent to scaling down the radial integral (5d/r/4f) to about 60% of the uncorrected HF value. The two-body correction has magnitude of approximately 25% relative to the uncorrected electric dipole moment. For ions in crystals, there is an additional one-body correction due to ligand polarization, whose magnitude is shown to be about 10% of the uncorrected electric dipole moment.