The full 207 Pb chemical shift (CS) tensor of lead in the mineral anglesite, PbSO 4 , was determined from orientation-dependent nuclear magnetic resonance (NMR) spectra of a large natural single crystal, using a global fit over two rotation patterns. The resulting tensor is characterised by the reduced anisotropy Δ δ = ( - 327 ± 4 ) ppm, asymmetry η C S = 0 . 529 ± 0 . 002 , and δ i s o = ( - 3615 ± 3 ) ppm, with the isotropic chemical shift δ i s o also verified by magic-angle spinning NMR on a polycrystalline sample. The initially unknown orientation of the mounted single crystal was included in the global data fit as well, thus obtaining it from NMR data only. By use of internal crystal symmetries, the amount of data acquisition and processing for determination of the CS tensor and crystal orientation was reduced. Furthermore, a linear correlation between the 207 Pb isotropic chemical shift and the shortest Pb–O distance in the co-ordination sphere of Pb 2 + solely surrounded by oxygen has been established for a large database of lead-bearing natural minerals.

Metal hydrides are an uprising compound class bringing up various functional materials. Due to the low X‐ray scattering power of hydrogen, neutron diffraction is often crucial to fully disclose the structural characteristics thereof. We herein present the second strontium nitridoborate hydride known so far, Sr13[BN2]6H8, formed in a solid‐state reaction of the binary nitrides and strontium hydride at 950 °C. The crystal structure was elucidated based on single‐crystal X‐ray and neutron powder diffraction in the hexagonal space group P63/m (no. 176), exhibiting a novel three‐dimensional network of [BN2]3− units and hydride anions connected by strontium cations. Further analyses with magic angle spinning (MAS) NMR and vibrational spectroscopy corroborate the presence of anionic hydrogen within the structure. Quantum chemical calculations reveal the electronic properties and support the experimental outcome. Sr13[BN2]6H8 expands the emerging family of nitridoborate hydrides, broadening the access to an open field of new, intriguing materials.

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In Nuclear Magnetic Resonance (NMR) spectroscopy, the isotropic chemical shift δiso is a measure of the electron density around the observed nuclide. For characterization of solid materials and compounds, it is desirable to find correlations between δiso and structural parameters such as coordination numbers and distances to neighboring atoms. Correlations of good quality are easier to find when the coordination sphere is formed by only one element, as the electron density is obviously strongly dependent on the atomic number. The current study is therefore restricted to nuclides in pure oxygen coordination. It is shown that the isotropic shift δiso correlates well with the average oxygen distances (as defined by the coordination sphere) for the nuclides 23Na (with spin I=3/2), 27Al (I=5/2), and 43Ca (I=7/2), using literature data for a range of periodic solids. It has been previously suggested for 207Pb (I=1/2) that δiso may alternatively be related to the shortest oxygen distance in the structure, and our study corroborates this also for the nuclides considered here. While the correlation with the minimal distance is not always better, it has the advantage of being uniquely defined. In contrast, the average distance is strongly dependent on the designation of the oxygen coordination sphere, which may be contentious in some crystal structures.

Cerussite, $$\hbox {PbCO}_3$$ PbCO 3 , like all members of the aragonite group, shows a tendency to form twins, due to high pseudo-symmetry within the crystal structure. We here demonstrate that the twin law of a cerussite contact twin may be established using only $$^{207}$$ 207 Pb-NMR spectroscopy. This is achieved by a global fit of several sets of orientation-dependent spectra acquired from the twin specimen, allowing to determine the relative orientation of the twin domains. Also, the full $$^{207}$$ 207 Pb chemical shift tensor in cerussite at room temperature is determined from these data, with the eigenvalues being $$\delta _{11} = (-2315\pm 1)$$ δ 11 = ( - 2315 ± 1 )  ppm, $$\delta _{22} = (-2492 \pm 3)$$ δ 22 = ( - 2492 ± 3 )  ppm, and $$\delta _{33} = (-3071 \pm 3)$$ δ 33 = ( - 3071 ± 3 )  ppm.