NUF₃ is identified as having a NU triple bond, as has been previously found (Andrews et al., Angew. Chem. Int. Ed., 2008, 47, 5366). By contrast, while previously reported calculations on PUF₃ and AsUF₃ (Andrews et al., Inorg. Chem., 2009, 48, 6594) gave a EU triple bond, our calculations suggest a single bond for both molecules, with antibonding π* and non-bonding 5f_U orbitals significantly occupied, and highly multiconfigurational wavefunctions. We propose this difference to be due to the smaller [6,6] active space used (σ, π, π* and σ*) in the previous studies. In our calculations, a [6,16] active space was employed in order to include uranium f-orbitals and pnictogen d-orbitals.

中文翻译：

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Hartree–Fock后EUF ₃中光气与铀结合的计算（E = N–Bi）†

NUF ₃被识别为上述的具有N ü三键，如先前已发现（安德鲁斯等人，Angew。化学式诠释。编，2008，47，5366）。与此相反，当在PUF先前报道计算₃和AsUF ₃（安德鲁斯等人，Inorg。化学式，2009，48，6594），得到A E ü三键，我们的计算表明对于两种分子是单键，与反键π *和非粘结5f _U轨道被大量占据，并且具有高度多配置的波函数。我们认为，这种差异是由于先前研究中使用的[6,6]较小的活动空间（σ，π，π*和σ*）引起的。在我们的计算中，为了包含铀的f轨道和光子的d轨道，使用了一个[6,16]的活动空间。