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The structural features of cobalt-based oxygen evolution catalysts are elucidated by combining high-field MAS NMR spectroscopy and DFT calculations. The superior photocatalytic activity of the heterogeneous system over its homogeneous counterpart is rationalised by the structural features. The higher activity is caused by a more favourable electron-withdrawing character of the framework. [ABSTRACT FROM AUTHOR]

An in‐depth analysis of the description of bonding within Cp′′′Ni‐cyclo‐P3 (Cp′′′=1,2,4‐tri‐tert‐butylcyclopentadienyl, [Ni]P3) employing X‐ray diffraction based multipolar modeling, density functional theory (DFT) as well as an "experimental wavefunction" obtained from X‐ray restrained wavefunction (XRW) fitting is presented. The results are compared to DFT calculations on white phosphorus – an isolobal analogue to [Ni]P3. A complementary bonding analysis shows insights into the reactivity of [Ni]P3. The isolobal principle is reflected in every aspect of our analysis and the employed methods seamlessly predict the differences in reactivity of [Ni]P3 and P4. Crystallographic modeling, solid‐state NMR, and DFT calculations describe the dynamic behavior of the cyclo‐P3 unit in the title molecule. [ABSTRACT FROM AUTHOR]

Two new ternary trielides Na7KTr4 (Tr=In, Tl) have been prepared by classical solid‐state reaction from the elements in tantalum ampoules. Both are isostructural to Na7RbTl4 and therefore crystallize in the orthorhombic space group Pbam, Pearson symbol oP96 (a=b=16.3283(2)/16.2860(6), c=11.3094(17)/11.2771(4), V=3015.25(8)/2991.07(18), Z=8, R1, wR2=0.0249, 0.0386/0.0447, 0.0608). The trielide subunit is built by two crystallographically independent [Tr4]8− tetrahedra. 23Na‐MAS‐Nuclear Magnetic Resonance (NMR) as well as EPR spectroscopy was employed to characterize the compounds further. DOS calculations showed a (pseudo) band gap at EF for both compounds. Dissolution experiments in liquid ammonia were carried out for the two alkali metal indides Na7KIn4 and Na2In according to the chemistry of group 14 and 15 Zintl anions. After evaporating the solvent, the remaining material was analyzed by powder X‐ray diffraction and proved the formation of NaIn and NaNH2. [ABSTRACT FROM AUTHOR]

Magnetic shielding depends on molecular structure and noncovalent interactions. This study shows that it is also measurably dependent on the electric field generated by surrounding molecules. This effect has been observed explicitly for 31P nucleus using the adduct under field approach. The results obtained indicate that the field strength experienced by molecules in crystals consisting of molecules with large dipole moments is similar to that in polar solvents. Therefore, magnetic shielding should explicitly depend on solvent polarity. It is important to note that this effect cannot be reproduced correctly within the polarizable continuum model approach. [ABSTRACT FROM AUTHOR]

Can the geometry of an acid-base complex in solution be reproduced in calculations using an implicit accounting for the solvent effect in the form of a macroscopic reaction field? The answer is, "Yes, it can." Is this field equal to the real electric field experienced by the complex in solution? The answer is, "No, it is not." How can the geometry be correct under wrong conditions? This question is answered using density functional theory modeling of geometric and NMR parameters of pyridine⋯HF⋯(HCF3)n adducts in the absence and presence of an external electric field. This adduct under field approach shows that the N⋯H distance is a function of the H–F distance whatever method is used to change the geometry of the latter. An explicit account for solute-solvent interactions is required to get a realistic value of the solvent reaction field. Besides that, this approach reveals how certain NMR parameters depend on the solvent reaction field, the solute-solvent interactions, and the geometry of the N⋯H–F hydrogen bond. For some of them, the obtained dependences are far from self-evident. [ABSTRACT FROM AUTHOR]

The effect of the local structure on the 31P NMR chemical shift tensor (CST) has been studied experimentally and simulated theoretically using the density functional theory gauge-independent-atomic-orbital approach. It has been shown that the dominating impact comes from a small number of noncovalent interactions between the phosphorus-containing group under question and the atoms of adjacent molecules. These interactions can be unambiguously identified using the Bader analysis of the electronic density. A robust and computationally effective approach designed to attribute a given experimental 31P CST to a certain local morphology has been elaborated. This approach can be useful in studies of surfaces, complex molecular systems, and amorphous materials. [ABSTRACT FROM AUTHOR]

A simultaneously protonated and functionalized silicide cluster [NHCDippCu(η4‐Si9)H]2− was detected and characterized in liquid ammonia by NMR spectroscopy. Key NMR results were corroborated by theoretical calculations. 1H‐NMR line‐widths at variable temperatures revealed that proton hopping in the metalated complex [NHCDippCu(η4‐Si9)H]2− is less pronounced than in the non‐complexed silicide [HSi9]3−. Besides [HSi9]3− and [NHCDippCu(η4‐Si9)H]2− also the unprotonated analogous cluster [NHCDippCu(η4‐Si9)]3− was detected in solution. In addition, a new 29Si‐NMR signal was obtained in the course of 29Si‐NMR studies that we assigned to [NHCDippCu(η4‐Si9)]3−. The isolation of crystals of (K[2.2.2]‐crypt)2K0.48Rb3.52[NHCDippCu(η4‐Si9)]2 prove the availability of the non‐protonated NHCDippCu(η4‐Si9) fragment in solution. To the best of our knowledge the detection of [NHCDippCu(η4‐Si9)H]2− represents the first case of a protonated and coinage metalated group 14 Zintl cluster in solution so far. [ABSTRACT FROM AUTHOR]

Structural knowledge on ubiquitous lithium salts in solution and in the crystalline state is of paramount importance for our understanding of many chemical reactions and of the electrolyte behaviour in lithium ion batteries. A bulky bidentate Si-based ligand (6) was used to create simplified model systems suitable for correlating structures of LiCl and LiPF6 complexes in the solid-state and in solution by combining various experimental, spectroscopic, and computational methods. Solution studies were performed using 1H DOSY, multinuclear variable temperature NMR spectroscopy, and quantum chemical calculations. [Ph2Si(2-CH2Py)2·LiCl]2 (3) dissociates into a monomeric species (9) in THF. For [Ph2Si(2-CH2Py)2·LiPF6]2 (11), low temperature NMR studies revealed an unprecedented chiral coordination mode (12) in non-coordinating solvents. [ABSTRACT FROM AUTHOR]