Although 2-Yb is diamagnetic this complex was obtained as a mixture together with other Yb(II)-containing products, thus the NMR spectra could also not be fully assigned. At 298 K the 1 H.NMR spectrum of a d8-toluene solution of 2-Yb showed the presence of THF, indicating that THF-solvated Yb or K complexes were present in this mixture, thus the broad resonance at 0.65 ppm that is likely due to the SiMe3 groups could not be reliably integrated. Similarly multiple signals were observed in the 31 P{ 1 H} NMR spectrum of this mixture at 298 K, with only a signal at -236.9 ppm that could be assigned to K{P(SiMe3)2} with reasonable confidence by comparison with an authentic sample. We do not observe a signal with well-resolved 1 JPYb coupling for unambiguous characterization of 171 Yb-bound P nuclei, though the broad signal at δP = -219.0 ppm is the predominant feature by approximate integration and is likely a Yb(II)-containing complex. We investigated the dynamic behavior of this mixture by performing variable temperature resolved with heating or cooling. The corresponding ). The 1 H and 13 C{ 1 H} NMR spectra of 3-Yb and 4-Yb were essentially unremarkable, save that the molecular symmetry in solution is higher than in the solid state, and that in the 13 C{ 1 H} NMR spectra the silyl group resonances are virtual triplets due to splitting by strongly coupled 100% abundant I = ½ Complex 1 H (δ) C{ H} (δ) Si DEPT90 (δ)