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NaCaO3 is (Cubic) Perovskite structured and crystallizes in the cubic Pm-3m space group. The structure is three-dimensional and consists of one sodium molecule and one CaO3 framework. In the CaO3 framework, Ca is bonded to six equivalent O atoms to form corner-sharing CaO6 octahedra. The corner-sharing octahedral tilt angles are 0°. All Ca–O bond lengths are 2.25 Å. O is bonded in a linear geometry to two equivalent Ca atoms.
NaYbO3 is (Cubic) Perovskite structured and crystallizes in the cubic Pm-3m space group. The structure is three-dimensional and consists of one sodium molecule and one YbO3 framework. In the YbO3 framework, Yb is bonded to six equivalent O atoms to form corner-sharing YbO6 octahedra. The corner-sharing octahedral tilt angles are 0°. All Yb–O bond lengths are 2.21 Å. O is bonded in a linear geometry to two equivalent Yb atoms.
(Na)2EuCuCl6 is High-temperature superconductor-derived structured and crystallizes in the cubic Fm-3m space group. The structure is three-dimensional and consists of eight sodium molecules and one EuCuCl6 framework. In the EuCuCl6 framework, Eu3+ is bonded to six equivalent Cl1- atoms to form EuCl6 octahedra that share corners with six equivalent CuCl6 octahedra. The corner-sharing octahedral tilt angles are 0°. All Eu–Cl bond lengths are 2.72 Å. Cu1+ is bonded to six equivalent Cl1- atoms to form CuCl6 octahedra that share corners with six equivalent EuCl6 octahedra. The corner-sharing octahedral tilt angles are 0°. All Cu–Cl bond lengths are 2.46 Å. Cl1- is bonded in a linear geometry to one Eu3+ and one Cu1+ atom.
(Na)2ScAuF6 crystallizes in the cubic Fm-3m space group. The structure is three-dimensional and consists of eight sodium molecules and one ScAuF6 framework. In the ScAuF6 framework, Sc3+ is bonded to six equivalent F1- atoms to form ScF6 octahedra that share corners with six equivalent AuF6 octahedra. The corner-sharing octahedral tilt angles are 0°. All Sc–F bond lengths are 2.02 Å. Au1+ is bonded to six equivalent F1- atoms to form AuF6 octahedra that share corners with six equivalent ScF6 octahedra. The corner-sharing octahedral tilt angles are 0°. All Au–F bond lengths are 2.43 Å. F1- is bonded in a distorted linear geometry to one Sc3+ and one Au1+ atom.
(Na)2YAgF6 crystallizes in the cubic Fm-3m space group. The structure is three-dimensional and consists of eight sodium molecules and one YAgF6 framework. In the YAgF6 framework, Y3+ is bonded to six equivalent F1- atoms to form YF6 octahedra that share corners with six equivalent AgF6 octahedra. The corner-sharing octahedral tilt angles are 0°. All Y–F bond lengths are 2.17 Å. Ag1+ is bonded to six equivalent F1- atoms to form AgF6 octahedra that share corners with six equivalent YF6 octahedra. The corner-sharing octahedral tilt angles are 0°. All Ag–F bond lengths are 2.40 Å. F1- is bonded in a linear geometry to one Y3+ and one Ag1+ atom.
NaBaIrH6 crystallizes in the cubic F-43m space group. The structure is three-dimensional and consists of four sodium molecules and one BaIrH6 framework. In the BaIrH6 framework, Ba2+ is bonded to twelve equivalent H1- atoms to form BaH12 cuboctahedra that share corners with twelve equivalent BaH12 cuboctahedra and faces with four equivalent IrH6 octahedra. All Ba–H bond lengths are 2.79 Å. Ir3+ is bonded to six equivalent H1- atoms to form IrH6 octahedra that share faces with four equivalent BaH12 cuboctahedra. All Ir–H bond lengths are 1.69 Å. H1- is bonded in a distorted T-shaped geometry to two equivalent Ba2+ and one Ir3+ atom.
(Na)2NaAuCl6 crystallizes in the cubic Fm-3m space group. The structure is three-dimensional and consists of eight sodium molecules and one NaAuCl6 framework. In the NaAuCl6 framework, Na1+ is bonded to six equivalent Cl1- atoms to form NaCl6 octahedra that share corners with six equivalent AuCl6 octahedra. The corner-sharing octahedral tilt angles are 0°. All Na–Cl bond lengths are 2.68 Å. Au3+ is bonded to six equivalent Cl1- atoms to form AuCl6 octahedra that share corners with six equivalent NaCl6 octahedra. The corner-sharing octahedral tilt angles are 0°. All Au–Cl bond lengths are 2.50 Å. Cl1- is bonded in a linear geometry to one Na1+ and one Au3+ atom.
(Na)2LiDyCl6 crystallizes in the cubic Fm-3m space group. The structure is three-dimensional and consists of eight sodium molecules and one LiDyCl6 framework. In the LiDyCl6 framework, Li1+ is bonded to six equivalent Cl1- atoms to form LiCl6 octahedra that share corners with six equivalent DyCl6 octahedra. The corner-sharing octahedral tilt angles are 0°. All Li–Cl bond lengths are 2.52 Å. Dy3+ is bonded to six equivalent Cl1- atoms to form DyCl6 octahedra that share corners with six equivalent LiCl6 octahedra. The corner-sharing octahedral tilt angles are 0°. All Dy–Cl bond lengths are 2.61 Å. Cl1- is bonded in a linear geometry to one Li1+ and one Dy3+ atom.
(Na)2LiCeCl6 is High-temperature superconductor-derived structured and crystallizes in the cubic Fm-3m space group. The structure is three-dimensional and consists of eight sodium molecules and one LiCeCl6 framework. In the LiCeCl6 framework, Li1+ is bonded to six equivalent Cl1- atoms to form LiCl6 octahedra that share corners with six equivalent CeCl6 octahedra. The corner-sharing octahedral tilt angles are 0°. All Li–Cl bond lengths are 2.53 Å. Ce3+ is bonded to six equivalent Cl1- atoms to form CeCl6 octahedra that share corners with six equivalent LiCl6 octahedra. The corner-sharing octahedral tilt angles are 0°. All Ce–Cl bond lengths are 2.72 Å. Cl1- is bonded in a linear geometry to one Li1+ and one Ce3+ atom.
(Na)2CuBiCl6 is High-temperature superconductor-derived structured and crystallizes in the cubic Fm-3m space group. The structure is three-dimensional and consists of eight sodium molecules and one CuBiCl6 framework. In the CuBiCl6 framework, Cu1+ is bonded to six equivalent Cl1- atoms to form CuCl6 octahedra that share corners with six equivalent BiCl6 octahedra. The corner-sharing octahedral tilt angles are 0°. All Cu–Cl bond lengths are 2.48 Å. Bi3+ is bonded to six equivalent Cl1- atoms to form BiCl6 octahedra that share corners with six equivalent CuCl6 octahedra. The corner-sharing octahedral tilt angles are 0°. All Bi–Cl bond lengths are 2.71 Å. Cl1- is bonded in a linear geometry to one Cu1+ and one Bi3+ atom.
(Na)2LiLaCl6 is High-temperature superconductor-derived structured and crystallizes in the cubic Fm-3m space group. The structure is three-dimensional and consists of eight sodium molecules and one LiLaCl6 framework. In the LiLaCl6 framework, Li1+ is bonded to six equivalent Cl1- atoms to form LiCl6 octahedra that share corners with six equivalent LaCl6 octahedra. The corner-sharing octahedral tilt angles are 0°. All Li–Cl bond lengths are 2.53 Å. La3+ is bonded to six equivalent Cl1- atoms to form LaCl6 octahedra that share corners with six equivalent LiCl6 octahedra. The corner-sharing octahedral tilt angles are 0°. All La–Cl bond lengths are 2.75 Å. Cl1- is bonded in a linear geometry to one Li1+ and one La3+ atom.
(Na)2LaCuCl6 is High-temperature superconductor-derived structured and crystallizes in the cubic Fm-3m space group. The structure is three-dimensional and consists of eight sodium molecules and one LaCuCl6 framework. In the LaCuCl6 framework, La3+ is bonded to six equivalent Cl1- atoms to form LaCl6 octahedra that share corners with six equivalent CuCl6 octahedra. The corner-sharing octahedral tilt angles are 0°. All La–Cl bond lengths are 2.75 Å. Cu1+ is bonded to six equivalent Cl1- atoms to form CuCl6 octahedra that share corners with six equivalent LaCl6 octahedra. The corner-sharing octahedral tilt angles are 0°. All Cu–Cl bond lengths are 2.51 Å. Cl1- is bonded in a linear geometry to one La3+ and one Cu1+ atom.
Introduction (120 words max) Understanding metal-cluster chemistry occuring at solvent boundaries in the aqueous and organic phases has applications in environments from cellular processes to nuclear fuel reprocessing. Transport of metal ions at the boundaries from aqueous to organic phases involves forming a metal-ligand complex, and wherever the initial metal coordination environment is significantly different from the final one, the metal transitions through a series of transient species in passing from one phase to another. Here an investigation of the role of coordination in the chemistry of the transient species using gas-phase measurements that are free of solvent effects to better understand the binding of complexes of metals with triphenylphosphine chalcogenide ligands, examining metal-ligand homo- and hetero-dimers to better understand transient species. Methods (120 word max) Mass spectrometry and collision induced dissociation (CID) experiments were performed with a Bruker (Billerica, MA, USA) micrOTOF-Q II quadrupole time-of-flight mass spectrometer (QTOF) and Bruker amaZon speed ETD (ion trap). High resolution/high mass accuracy spectra were generated using the QTOF. External calibration was performed with Agilent (Santa Clara, CA, USA) ESI-L Low Concentration tuning mix. Both mass spectrometers were equipped with either the electrospray ionization source or nanospray sources. Metal samples were prepared between 40 – 60 uM of the metal-ligand complex in 25% water and 75% acetonitrile. Metal-ion clusters were isolated and subjected to collision induced dissociation. Density functional theory calculations were performed. Preliminary Data or Plenary Speakers Abstract (300 words max) Metal ion clusters with triphenylphosphine chalcogenide ligands were observed for group I metals with triphenylphosphine chalcogenide samples in the mass spectrum upon electrospray ionization. For each metal ligand complex of interest, the parent ion was isolated and collision induced dissociation fragmentation spectra were acquired. We observed clusters of group I metal with triphenylphosphine oxide, triphenyl phosphine sulfide, and triphenylphosphine selenide, with homodimers and heterodimer formation. In samples where the ligands were mixed, we observed mixed sodium ligand clusters at varying amounts. These mixed ligand clusters were fragmented. Metal clusters of mixed ligand dimers containing triphenylphosphine oxide showed preferential loss of the other ligand, either triphenylphosphine sulfide or triphenyl selenide. In samples with mixed triphenylphosphine sulfide and triphenylphosphine selenium ligands, sodium bound similarly between the ligands, and losses were more evenly split, showing loss ratio upon CID with losses of triphenylphosphine sulfide:triphenylphosphine selenide 43:57 ratio observed on CID. These results suggest that the oxide binds significantly more strongly than either the selenium or sulfur triphenylphosphine ligand, and the sulfur and selenium ligands are more evenly bound. Calculations were performed using density functional theory to calculate likely structures and bond energies between the group I metal and the ligands. Novel Aspect Novel analysis of sodium bound dimers with chalcogenide triphenylphosphine ligands were investigated using mass spectrometry and theoretical calculations.
Electrochemically driven chemical transformations play the key role in controlling storage of energy in chemical bonds and subsequent conversion to power electric vehicles and consumer electronics. The promise of coupling anionic oxygen redox with cationic redox to achieve a substantial increase in capacities has inspired research in a wide range of electrode materials. A key challenge is that these studies have focused on polycrystalline materials, where it is hard to perform precise structural determinations, especially related to the location of light atoms. Here a different approach is utilized and a highly ordered single crystal, Na 2-x IrO 3 is harnessed, to explore the role of defects and structural transformations in layered transition metal oxide materials on redox-activity, capacity, reversibility, and stability. Within a combined experimental and theoretical framework, it is demonstrated that 1) it is possible to cycle Na 2-x IrO 3 , offering proof of principle for single-crystal based batteries 2) structural phase transitions coincide with Ir 4+ /Ir 5+ redox couple with no evident contribution from anionic redox 3) strong irreversibility and capacity fade observed during cycling correlates with the Na + migration resulting in progressive growth of an electrochemically inert O 3 -type NaIrO 3 phase.
Abstract We present a record 20‐W continuous‐wave output power membrane‐external‐cavity surface‐emitting laser (MECSEL) double‐bonded to silicon carbide (SiC) heat spreaders emitting around 1178 nm. We achieved a maximum slope efficiency of 27.7% and an optical‐to‐optical efficiency of 26.7%. By utilising an intracavity birefringent filtre, the wavelength was tuned over 75 nm and maximum output power of 12.7 W was recorded at 1178 nm. This study shows the potential of MECSELs to achieve high‐performance and cost‐effective optically pumped semiconductor disk lasers targeting applications in sodium guide stars.
Alkaline iron (Fe) batteries are attractive due to the high abundance, low cost, and multiple valent states of Fe but show limited columbic efficiency and storage capacity when forming electrochemically inert Fe 3 O 4 on discharging and parasitic H 2 on charging. Herein, sodium silicate is found to promote Fe(OH) 2 /FeOOH against Fe(OH) 2 /Fe 3 O 4 conversions. Electrochemical experiments, operando X-ray characterization, and atomistic simulations reveal that improved Fe(OH) 2 /FeOOH conversion originates from (i) strong interaction between sodium silicate and iron oxide and (ii) silicate-induced strengthening of hydrogen-bond networks in electrolytes that inhibits water transport. Furthermore, the silicate additive suppresses hydrogen evolution by impairing energetics of water dissociation and hydroxyl de-sorption on iron surfaces. In conclusion, this new silicate-assisted redox chemistry mitigates H 2 and Fe 3 O 4 formation, improving storage capacity (199 mAh g -1 in half-cells) and coulombic efficiency (94 % after 400 full-cell cycles), paving a path to realizing green battery systems built from earth-abundant materials.
(Na)2(AlSiO4)2O2 is Cuprite-derived structured and crystallizes in the cubic F-43m space group. The structure is three-dimensional and consists of four sodium molecules, four water molecules, and one AlSiO4 framework. In the AlSiO4 framework, Al is bonded to four equivalent O atoms to form AlO4 tetrahedra that share corners with four equivalent SiO4 tetrahedra. All Al–O bond lengths are 1.73 Å. Si is bonded to four equivalent O atoms to form SiO4 tetrahedra that share corners with four equivalent AlO4 tetrahedra. All Si–O bond lengths are 1.62 Å. O is bonded in a linear geometry to one Al and one Si atom.
Arguably the most ubiquitous construction material in modern civilization, concrete is enabling the development of megacities around the globe together with increasing living standards in developing nations. However, the exact formation mechanisms of the strength-giving calcium-rich gels remain a topic of debate. Using density functional modeling, we simulate the fundamental solution-based building blocks of cement hydrates (calcium ions and silicate and aluminate monomers) and their propensity to form pair-wise complexes with bonding environments characteristic of those found in calcium-silicate-hydrate, calcium-alumino-silicate-hydrate and sodium-containing calcium-alumino-silicate-hydrate gels, as assessed from Gibbs free energies of chemical reactions. By accurately simulating the high pH pore solution chemistry in Portland cements and related systems, along with discrete solvation of the species, we hypothesize potential early age formation routes of the gels and discuss limitations and future work associated with this approach.