Oxidation states, geometries, and electronic structures of plutonium tetroxide PuO4 isomers: is octavalent Pu viable?
Oxidation states, geometries, and electronic structures of plutonium tetroxide PuO4 isomers: is octavalent Pu viable?
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DOI：
10.1021/ic402170q
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发表时间：
2013-11
影响因子：
4.6
通讯作者：
Wei Huang;Wen-Hua Xu;Jing Su;W. Schwarz;Jun Yu Li
中科院分区：
文献类型：
--
作者：
Wei Huang;Wen-Hua Xu;Jing Su;W. Schwarz;Jun Yu Li
在中性化合物中，元素周期表中所有元素的最高已知氧化态是+VIII。虽然PuO 4被认为是一种奇特的Pu（+VIII）配合物，但我们在这里已经表明，对于PuO 4，不存在八价RuO 4和OsO 4的稳定电子同系物，即使Pu与Ru和Os具有相同的八价电子数。我们发现PuO_4的基态是一个五重的（5）C_2 v-（PuO_2）（+）（O_2）（-）配合物，其主要价态是一个（f（3））钚基（V）单元，与一个超氧（π ~*（3））O_2（-）配体松散耦合。这种稳定的异构体很可能作为一种瞬态物质被检测到，而先前提出的平面（1）D4 h-Pu（VIII）O 4异构体只是亚稳态的。通过电子结构分析，解释和合理化的键和氧化态。我们已经预测的电子和振动光谱的特性，以帮助未来的实验鉴定（PuO 2）（+）（O2）（-）的红外光谱，紫外可见光谱，电离光谱。
In neutral chemical compounds, the highest known oxidation state of all elements in the Periodic Table is +VIII. While PuO4 is viewed as an exotic Pu(+VIII) complex, we have shown here that no stable electronic homologue of octavalent RuO4 and OsO4 exists for PuO4, even though Pu has the same number of eight valence electrons as Ru and Os. Using quantum chemical approaches at the levels of quasi-relativistic DFT, MP2, CCSD(T), and CASPT2, we find the ground state of PuO4 as a quintet (5)C2v-(PuO2)(+)(O2)(-) complex with the leading valence configuration of an (f(3))plutonyl(V) unit, loosely coupled to a superoxido (π*(3))O2(-) ligand. This stable isomer is likely detectable as a transient species, while the previously suggested planar (1)D4h-Pu(VIII)O4 isomer is only metastable. Through electronic structure analyses, the bonding and the oxidation states are explained and rationalized. We have predicted the characteristics of the electronic and vibrational spectra to assist future experimental identification of (PuO2)(+)(O2)(-) by IR, UV-vis, and ionization spectroscopy.