¹H chemical shift anisotropy: a high sensitivity solid-state NMR dynamics probe for surface studies?

Abstract

Dynamics play significant roles in chemistry and biochemistry—molecular motions impact both large- and small-scale chemical reactions in addition to biochemical processes. In many systems, including heterogeneous catalysts, the characterization of...

Predicting 51V nuclear magnetic resonance observables in molecular crystals

“…Similar to isotropic chemical shielding, the chemical shift anisotropy is a highly sensitive probe of structure and dynamics [75] . Figure 2b illustrates the convergence behavior of CSA predictions with respect to QM region size.…”

“…Similar to isotropic chemical shielding, the chemical shift anisotropy is a highly sensitive probe of structure and dynamics. [75] Figure 2b illustrates the convergence behavior of CSA predictions with respect to QM region size. Comparing with the results in the previous sections highlights several similarities between predicted 51 V F I G U R E 3 Error distribution for the predicted CS tensor principal values obtained using planewave DFT (grey), GIPAWcorrected methods using a two-body fragment correction (GIPAW + FC), and two-body fragment calculations (Fragment).…”

Multiplex Detection of Multiple-Quantum/Single-Quantum NMR Correlation Spectra

“…All samples were prepared as described in earlier publications. , Solid-state NMR experiments were performed using a Bruker AVANCE III 600 MHz NMR spectrometer equipped with either a Varian 1.6 mm (AL-SiO 2 ) or a JEOL 0.75 mm fast-MAS probe. In the experiments utilizing the 1.6 mm rotors, the MAS rate was set to 39.6825 kHz, which was increased to 83.333 kHz in the experiments utilizing the smaller diameter rotors.…”

“…The last sample we investigated is a Cp 2 ZrOMe/SiO 2 surface organometallic complex whose dynamics were recently investigated by 1 H chemical shift anisotropy recoupling methods. 41 It was suggested, through a combination of experiments and molecular dynamics simulations, that the clustering of Zr centers on the silica surface is responsible for limiting the rotational motions of the complex. It is thus of interest to apply the multiplex MQ/1Q correlation experiment to this sample to reveal whether we can detect the clustering of Zr centers.…”

Using Abundant 1H Polarization to Enhance the Sensitivity of Solid-State NMR Spectroscopy

“…In addition to MQ coherences, the small chemical shift anisotropy (CSA) of protons can also be recovered under fast MAS conditions, − which can be utilized to obtain deep insights into hydrogen bonding interactions, molecular packings, or even dynamics . However, the regular γ-encoded R -symmetry based pulse sequence typically only recouple the | m | = 2 terms ( m is the space component), since recoupling | m | = 1 terms will unavoidably reintroduce homonuclear proton dipolar couplings .…”