Benchmark study of DFT with Eu and Np Mossbauer isomer shifts using second-order Douglas-Kroll-Hess Hamiltonian
Benchmark study of DFT with Eu and Np Mossbauer isomer shifts using second-order Douglas-Kroll-Hess Hamiltonian
复制标题
使用二阶 Douglas-Kroll-Hess 哈密顿量对具有 Eu 和 Np 穆斯堡尔异构体位移的 DFT 进行基准研究
DOI：
10.1007/s10751-018-1495-1
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发表时间：
2018
期刊：
影响因子：
--
通讯作者：
Satoru Nakashima
中科院分区：
文献类型：
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作者：
Masashi Kaneko;Masayuki Watanabe;Sunao Miyashita;Satoru Nakashima
我们用TPSS交换相关泛函优化了纯DFT和精确Hartree-Fock之间的交换能量混合比，通过对151Eu和237Np核素穆斯堡尔异构体位移的实验数据的数值标杆，精确地估算了f-嵌段配合物中的配位键。采用分段全电子相对论收缩基组的二阶Douglas-Kroll-Hess哈密顿量，计算了Eu(III)和Np(IV)体系在Eu和Np核上的电子密度，即接触密度。通过改变Hartree-Fock交换参数的混合比从0到100%，以10%为间隔，比较了它们的异构体位移的均方根值。结果表明，对于Eu和NP基准体系，当混合比例分别为30%和60%时，偏差最小。Mulliken的自旋布居分析表明，Eu和NP络合物的金属-配位键的共价性都随着Hartree-Fock交换混合物的增加而降低。
We optimized a mixing ratio of exchange energy between pure DFT and exact Hartree-Fock using TPSS exchange-correlation functional to estimate the accurate coordination bonds in f-block complexes by numerically benchmarking with the experimental data of Mössbauer isomer shifts for151Eu and237Np nuclides. Second-order Douglas-Kroll-Hess Hamiltonian with segmented all-electron relativistically contracted basis set was employed to calculate the electron densities at Eu and Np nuclei, i.e. contact densities, for each five complexes for Eu(III) and Np(IV) systems. We compared the root mean square deviation values of their isomer shifts between experiment and calculation by changing the mixing ratio of Hartree-Fock exchange parameter from 0 to 100% at intervals of 10%. As the result, it was indicated that the mixing ratio of 30 and 60% for Eu and Np benchmark systems, respectively, gives the smallest deviation values. Mulliken’s spin population analysis indicated that the covalency in the metal-ligand bonds for both Eu and Np complexes decreases with increasing the Hartree-Fock exchange admixture.