Detailed analysis of the TIMES and TIMES0 high-resolution MAS methods for high-resolution proton NMR.

摘要: Abstract We analyze and compare the specifications of TIMES 0 proton high-resolution NMR methods for solid-state samples. This comparison is performed in terms resolution versus magic-angle spinning (MAS) speed, ν R , rf-field amplitude, 1 tilt-angle effective rf-field, θ p . The chemical-shift homo-nuclear dipolar scaling factors are calculated both methods. For all MAS speeds, best always observed with  ≈ 120–130 kHz. At slow speed (  ⩽ 10 kHz), a P  ≈ 90°. moderate (15 ⩽   ⩽ 35 kHz),  ≈ 55° gives resolution. higher  ⩾ 60 kHz), obtained  ⩽ 40°; but we then recommend owing to its simpler set-up. also show that addition usual high regime  ≈ 120–130 kHz), another low rf-regime  ≈ 40–50 kHz) exists at than  ⩾ 60 kHz, which good H should be useful multi-dimensional analyses bio-molecules detection under high-resolution, order limit heating sample.