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A new quaternary phosphide composed of a Cu–Mg–P framework hosting Ba and Mg cations is synthesized and characterized.
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We show that vacancy creation and relativistic spin–orbit coupling play a crucial role in promoting fast Mg-ion conduction of Mg 3 Bi 2 .
The binary bismuthides Nd 3 Bi 7 and Sm 3 Bi 7 were synthesized and structurally characterized for the first time. Here, the results from the calorimetric analysis show that both compounds are stable only up to about 500 °C, which may explain why they were overlooked during the original assessment of the corresponding phase diagrams.
In molecular solids derived from Prussian blue, intermetallic charge transfer is fostered through a cyano bridge two metal ions. In this paper, isostructural trivalent lanthanide and tetravalent actinide Prussian blue analogs' valence orbitals are probed by soft X-ray absorption measurements.
Polycyclic aromatic hydrocarbons (PAHs) may comprise up to 20% of the carbon budget in our galaxy and most PAHs condense onto water-rich icy grain mantles. Benzene–water clusters have been invoked as model systems for studying the photo-processing of water ice mantles containing PAHs. However, there is a paucity of information on larger aromatics, where the extended π cloud could affect photo-processing. Here in this study, tunable vacuum ultraviolet (VUV) photoionization of naphthalene–water clusters N x (H 2 O) y (N denotes naphthalene) is performed using synchrotron radiation and analyzed by reflectron time-of-flight mass spectrometry. Naphthalene clusters up to x = 4 are generated as are naphthalene–water clusters up to y = 25. At low photon energy (<11 eV), the naphthalene moiety is ionized and there is no proton transfer from N + to the water sub-cluster, which is very different from the benzene–water system. Protonated products, N[(H 2 O) x H] + and OH radical addition product (NOH)[(H 2 O) x H] + are generated above 11 eV, suggesting that water sub-clusters dominate the dynamics at high photon energies. Ab initio calculations are performed to decipher the experimental results. Energetics of the neutral structures N(H 2 O) 1–4 and their photoionized counterparts are calculated, including ionization on the N moiety as well as on the water sub-cluster. Energy decomposition analysis (EDA) is performed to understand trends in the binding between the naphthalene and the water sub-cluster in the ionized species.
Calculated DOS of a-Si:H close to the band gap for different H concentrations in the case of (a) thermodynamic and (b) kinetic H addition.
The local valence orbital structure of solid glycine, diglycine, and triglycine is studied using soft X-ray emission spectroscopy (XES), resonant inelastic soft X-ray scattering (RIXS) maps, and spectra calculations based on density-functional theory. Using a building block approach, the contributions of the different functional groups of the peptides are separated. Cuts through the RIXS maps furthermore allow monitoring selective excitations of the amino and peptide functional units, leading to a modification of the currently established assignment of spectral contributions. The results thus paint a new-and-improved picture of the peptide bond, enhance the understanding of larger molecules with peptide bonds, and simplify the investigation of such molecules in aqueous environment.
In this work, we report two anionic diphosphametallocenates, [K(2.2.2-crypt)][M(PC 4 Me 4 ) 2 ] (M = Cr, 2-Cr ; Fe, 2-Fe ). Both are low-spin ( S = ½) by EPR spectroscopy and SQUID magnetometry. This contrasts the high-spin ( S = ) ferrocenate, [K(2.2.2-crypt)][Fe(C 5 H 2 -1,2,4- t Bu) 2 ] ( 4-Fe ). Quantum chemical calculations suggest this is due to significant differences in ligand field splitting of the d-orbitals which also explain structural features in the 2-M complexes.
Valence bond theory reveals the nature of the OC–C bond in carbon suboxide and related allene compounds.
In situ X-ray absorbance spectroscopy measurements show that encapsulating cobalt phthalocyanine within coordinating polymers leads to axial ligation of Co and results in enhanced rates for electrocatalytic CO 2 reduction.
A series of cerium( iv ) mixed-ligand guanidinate-amide complexes, {[(Me 3 Si) 2 NC(N i Pr) 2 ] x Ce IV [N(SiMe 3 ) 2 ] 3− x }+ ( x = 0−3), was prepared by chemical oxidation and studied spectroscopically and computationally, revealing trends in 4f/5d orbital occupancies.
Active site FeV-cofactor of the V-nitrogenase and the EPR spectrum of the reduced cofactor showing 51 V-hyperfine coupling.
The actinide allenylidenes [{(NR 2 ) 3 }An(CCCPh 2 )] − (An = U, Th, R = SiMe 3 ) feature significant ligand-to-metal donation bonding and partial AnC double bond character.
Ce( iv ) complexes with multiple bonds display similar f 0 fractions, but different f/d hybridization, 5d-orbital energies, and TIP levels.
Reaction of [UI 2 (HMPA) 4 ]I with potassium anthracenide gives the unprecedented arenide-sandwich complex U(η 6 -C 14 H 10 )(η 4 -C 14 H 10 )(HMPA) 2 . CASSCF calculations indicate the U–C bonding to solely consist of π-interactions.
Hard X-ray photoelectron spectroscopy reveals the (Cd,Zn)S:Ga/CuSbS 2 thin-film solar cell interface to be heavily intermixed resulting in a ‘cliff’-like conduction band offset.
Using strain engineering to optimize novel heterostructure materials to produce hydrogen from water.