【摘 要】
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To provide an insight into chirality of inorganic complexes,cis-bis(imido)uranium iodides,cis-U(NPh)2(THF)3I2(3Ph1 and 3Ph2)and cis-U(NPh)2(THF)2I2(2Ph1 and 2Ph2)have been examined using density funct
【机 构】
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Key Laboratory of Functional Inorganic Material Chemistry of Education Ministry,School of Chemistry
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To provide an insight into chirality of inorganic complexes,cis-bis(imido)uranium iodides,cis-U(NPh)2(THF)3I2(3Ph1 and 3Ph2)and cis-U(NPh)2(THF)2I2(2Ph1 and 2Ph2)have been examined using density functional theory(DFT)and time-dependent DFT.Total system energies,geometry parameters and vibrational spectra were calculated to be close between respective enantiomers.The difference of U=N distances.Analyses on electronic structures in the tetrahydrofuran solution reveal that these mirror complexes show mixed π(U=N)and π(Ph)character for HOMO and HOMO-1; lone pair electrons of iodine are dominant in energetically lower occupied orbitals.The orbital energies were calculated to be slightly different between enantiomers,which causes difference in corresponding electronic transitions and is further reflected in electronic spectra.The calculated exciton-coupled circular dichroism(ECCD)spectra of 2Ph1 and 2Ph2 exhibit a complete mirror symmetry.We also calculated experimentally known trans-U(NPh)2(THF)3I2(trans-3Ph).The comparison among calculated results of trans-3Ph,3Ph1 and 3Ph2 indicates that the cis/trans-isomerism affects their structural and electronic properties more significantly than the chirality.
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