103Rh-NMR bei 9,4 T - Verbesserter Nachweis infolge verkürzter Relaxationszeiten und selektivem Polarisationstransfer / 103Rh NMR at 9.4 T - Improved Signal Detection due to Shortened Relaxation Times and Selective Polarisation Transfer

Abstract

Abstract At 9.4 T the I03Rh relaxation times (T ,) of unsym metrical organorhodium com pounds of the type LR h(7r-ligand) 2 are in the order of seconds, and relaxation is dominated by the Chemical Shift Anisotropy mechanism. In symmetrical complexes like (acac)3Rh (7), T, of 103Rh is considerably longer and dominated by the Spin Rotation mechanism. Through this effect, together with selective polarisation transfer via the Rh olefin-proton spin-spin couplings at high magnetic fields, a significantly improved detection of the insensitive Rh nucleus results