NMR Crystallography: Evaluation of Hydrogen Positions in Hydromagnesite by ¹³C{¹H} REDOR Solid‐State NMR and Density Functional Theory Calculation of Chemical Shielding Tensors

Abstract

This is the author manuscript accepted for publication and has undergone full peer review but has not been through the copyediting, typesetting, pagination and proofreading process, which may lead to differences between this version and the Version of Record.

Enabling materials informatics for 29Si solid-state NMR of crystalline materials

“…Prediction of the full diagonalized tensor is useful for planning experiments, both under static solid-state or magic-angle-spinning (MAS) NMR conditions, that will enable accurate extraction of these values. As we have shown in a separate 13 C study 6 , determination of the chemical shift tensor values enabled refinement of the H positions in a polycrystalline sample.…”

“…Determination of lattice parameters, symmetry, and coordinates of moderate-to high-Z species in the lattice is relatively straightforward, making XRD a powerful and versatile analytical tool. As the demand for accuracy of atomic coordinates increases, structures proposed based only on XRD have been shown to lack accuracy for lighter elements, such as H [5][6][7][8] . In this case, other experimental techniques like neutron diffraction and recently NMR have been employed to lend accuracy.…”

Learning to Make Chemical Predictions: The Interplay of Feature Representation, Data, and Machine Learning Methods

“…Because they are sensitive to their functional groups, detailed geometries, and chemical environments, they allow for prediction of solution-phase protein structures or for the identification or verification of the structure of chemical compounds in the crystalline phase. 53 The connection between NMR chemical shifts to structural or dynamical properties, while true in principle, is nevertheless sometimes difficult to reveal in practice through direct assignment of the spectrum. One solution to this problem is to rely on expensive QM methods that often can accurately predict spectral observables from structure of small molecular fragments.…”

Discovery of an Environmentally Friendly Water-Soluble Luminous Material with Interstitial Site Occupancy

“…As shown in Figure a, the 1 H NMR spectrum of KHF 2 shows four signals at 1.575, 1.962, 5.095, and 6.804 ppm. Of these, the peak at 6.804 ppm corresponds to the O–H–O band of H 2 O in the air adsorbed by KHF 2 , while the peaks at 1.575, 1.962, and 5.095 ppm are consistent with the three different F–H–F crystallographic sites in the host. − Besides, the 1 H NMR spectrum of KHF 2 :0.197%Mn 4+ also has close signals at 1.508, 1.897, 4.962, and 6.984 ppm as KHF 2 , suggesting that the degree of ordering of the materials is mildly effected by Mn 4+ codoping, whereas the chemical shift of the 1 H NMR spectrum presents a slight shift after the doping of Mn 4+ and Mn 4+ ions enter into the interstitial site, causing the chemical environment change of the surrounding H + ions . Moreover, the 19 F NMR spectra of KHF 2 and KHF 2 :Mn 4+ exhibit major signals around −165.233 and −169.850 ppm (Figure S3); the chemical shift phenomenon also indicates that the chemical environment of the F – ions changes slightly because of the Mn 4+ doping. , These results prove that an interstitial Mn 4+ ion site is successfully created in the KHF 2 host.…”