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High-Spin Iron(VI), Low-Spin Ruthenium(VI), and Magnetically Bistable Osmium(VI) in Molecular Group 8 Nitrido Trifluorides NMF₃.

ABSTRACT: Pseudo-tetrahedral nitrido trifluorides N≡MF₃ (M=Fe, Ru, Os) and square pyramidal nitrido tetrafluorides N≡MF₄ (M=Ru, Os) were formed by free-metal-atom reactions with NF₃ and subsequently isolated in solid neon at 5 K. Their IR spectra were recorded and analyzed aided by quantum-chemical calculations. For a d² electron configuration of the N≡MF₃ compounds in C_3v symmetry, Hund's rule predict a high-spin ³ A₂ ground state with two parallel spin electrons and two degenerate metal d(δ)-orbitals. The corresponding high-spin ³ A₂ ground state was, however, only found for N≡FeF₃ , the first experimentally verified neutral nitrido Fe^VI species. The valence-isoelectronic N≡RuF₃ and N≡OsF₃ adopt different angular distorted singlet structures. For N≡RuF₃ , the triplet ³ A₂ state is only 5 kJ mol^-1 higher in energy than the singlet ¹ A' ground state, and the magnetically bistable molecular N≡OsF₃ with two distorted near degenerate ¹ A' and ³ A" electronic states were experimentally detected at 5 K in solid neon.

SUBMITTER: Stuker T

PROVIDER: S-EPMC8457171 | biostudies-literature |

REPOSITORIES: biostudies-literature

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