US EPA

4697300 

Journal Article 

Theoretical Studies of Structural Design and Stability of Double-layered Sandwich-like Tetrapyrrolic Uranium Complexes 

Tian Linfei; Zhang Chunhua; Qu Ning; Bi Yanting; Zhang Hongxing; Pan Qingjiang 

2018 

1 

Gaodeng Xuexiao Huaxue Xuebao / Chemical Journal of Chinese Universities
ISSN: 0251-0790 

39 

4 

749-757 

10.7503/cjcu20170463 

WOS:000435334500021 

To explore the interaction between tetrapyrrolic ligand and low-valent uranium ion, double-layered Sandwich-like complexes PzU(m)PzU(m)Pz(labeled as U(2)(m)Pz(3); m=III and IV, Pz=porphyrazine) were designed according to the single-layered (PcUPc)-Pc-VI(Pc=phthalocyanine) that was experimentally synthesized. Relativistic density functional theory(RDFT) was used to examine structures, stability and chemical bonding. It is shown that complexes U(2)(m)Pz(3) have the quintet ground state. Steric configurations are found to have a little effect on isomeric stability, while electron-spin states play more important role. Topological analyses of electron density suggest weakly polarized covalent character for U-N bonds. Tetravalent diuranium complex possesses four U(5f)-character high-lying occupied orbitals, in accordance with U-VI 5f-electron number counting. Differently, some electron transfer from uranium to ligand(Pz) is unraveled for the trivalent complex, leading to more ligand contribution to frontier molecular orbitals. 

Sandwich-like tetrapyrrolic uranium complex; Stability of isomer; Quantum theory of atoms in molecule( QTAIM); Electronic structure; Relativistic density functional theory