| Popis: |
The two-coordinate metal amide complexes V{N(SiMePh₂)₂}₂ (1) and Cr{N(SiMe₂Ph)₂}₂ (2) were synthesized by reaction of two equivalents of LiN(SiMePh₂)₂ with VI₂(THF)₄ or CrCl₂(THF)₂ in n-hexane. Their crystal structures showed that they have bent coordination, N-V-N = 137.0(4)°, N-Cr-N = 139.19(5)°, at the metals. The vanadium complex (1) displayed no tendency to isomerize as previously observed for some V(II) amido complexes. Curie fits of SQUID magnetic measurements afforded magnetic moments of 3.36 (1) and 4.68 (2) μB, consistent with high-spin configurations. These values are lower than the spin-only values of 3.88 and 4.90 μB expected for d³ and d⁴ complexes, suggesting a significant unquenched orbital angular momentum contribution to the overall moment, which is lower as a result of the positive spin-orbit coupling constants. |
