A comprehensive characterization of thiophosgene in the solid state.

Thiophosgene is one of the principal C=S building blocks in synthetic chemistry. At room temperature, thiophosgene is a red liquid. While its properties in the liquid and gaseous states are well known, a comprehensive characterization of thiophosgene in its solid state is presented here.

A high-power 4 × 4: crystallographic and electrochemical insights into a novel Wadsley-Roth anode NbTiWO.

A novel 4 × 4 Wadsley-Roth block phase, NbTiWO, has been prepared and its structure determined through Neutron and X-ray diffraction studies. Electrochemical testing indicated excellent high rate performance, with a returned delithiation capacity of 184 (4) mA h g at a current of 2 A g.

Configurational entropy of ice XIX and its isotope effect.

Ice XIX is a partly hydrogen-ordered polymorph related to disordered ice VI, similar to ice XV. We here investigate the order-order-disorder sequence ice XIX→ice XV→ice VI based on calorimetry at ambient pressure both for DO and HO-ice XIX. From these data we extract configurational entropy differences between ice XIX, ice XV and ice VI.

Origin of Polarization in Bismuth Sodium Titanate-Based Ceramics.

The classical view of the structural changes that occur at the ferroelectric transition in perovskite-structured systems, such as BaTiO, is that polarization occurs due to the off-center displacement of the B-site cations. Here, we show that in the bismuth sodium titanate (BNT)-based composition 0.2(BaSrTiO)-0.

A fast ceramic mixed OH/H ionic conductor for low temperature fuel cells.

Low temperature ionic conducting materials such as OH and H ionic conductors are important electrolytes for electrochemical devices. Here we show the discovery of mixed OH/H conduction in ceramic materials. SrZrYO exhibits a high ionic conductivity of approximately 0.

Centrohexaindane, a Unique Polyaromatic Hydrocarbon Bearing the Rare C (C ) Core: Inelastic Neutron Scattering, Infrared and Raman Spectroscopy.

The structure and vibrational spectroscopy of centrohexaindane, 1, was investigated. This unusual molecule has a quaternary carbon atom that is coordinated to four further such quaternary carbon atoms as its core, each pair of which is bonded to an ortho-phenylene unit. Previous NMR studies have shown that the molecule has tetrahedral (T ) symmetry in solution.

Antiferroelectric-like Behavior in a Lead-Free Perovskite Layered Structure Ceramic.

Antiferroelectric (AFE) materials have been intensively studied due to their potential uses in energy storage applications and energy conversion. These materials are characterized by double polarization-electric field (-) hysteresis loops and nonpolar crystal structures. Unusually, in the present work, SrLaTaTiO (STLT32), SrLaTaTiO (STLT36), and SrCaTaO (SCT15), lead-free perovskite layered structure (PLS) materials, are shown to exhibit AFE-like double - hysteresis loops despite maintaining a polar crystal structure.

Structure and Spectroscopy of Iron Pentacarbonyl, Fe(CO).

We have re-investigated the structure and vibrational spectroscopy of the iconic molecule iron pentacarbonyl, Fe(CO), in the solid state by neutron scattering methods. In addition to the known 2/ structure, we find that Fe(CO) undergoes a displacive ferroelastic phase transition at 105 K to a 1̅ structure. We propose that this is a result of certain intermolecular contacts becoming shorter than the sum of the van der Waals radii, resulting in an increased contribution of electrostatic repulsion to these interactions; this is manifested as a strain that breaks the symmetry of the crystal.

Ab initio simulations of α- and β-ammonium carbamate (NH·NHCO), and the thermal expansivity of deuterated α-ammonium carbamate from 4.2 to 180 K by neutron powder diffraction.

Experimental and computational studies of ammonium carbamate have been carried out, with the objective of studying the elastic anisotropy of the framework manifested in (i) the thermal expansion and (ii) the compressibility; furthermore, the relative thermodynamic stability of the two known polymorphs has been evaluated computationally. Using high-resolution neutron powder diffraction data, the crystal structure of α-ammonium carbamate (ND·NDCO) has been refined [space group Pbca, Z = 8, with a = 17.05189 (15), b = 6.

Structural Evolution in BiNbO.

The sequence of transitions between different phases of BiNbO has been thoroughly investigated and clarified using thermal analysis, high-resolution neutron diffraction, and Raman spectroscopy. The theoretical optical phonon modes of the α-phase have been calculated. Based on thermoanalytical data supported by density functional theory (DFT) calculations, the β-phase is proposed to be metastable, while the α- and γ-phases are stable below and above 1040 °C, respectively.

Structural characterization of ice XIX as the second polymorph related to ice VI.

Ice polymorphs usually appear as hydrogen disorder-order pairs. Ice VI has a wide range of thermodynamic stability and exists in the interior of Earth and icy moons. Our previous work suggested ice β-XV as a second polymorph deriving from disordered ice VI, in addition to ice XV.

Phenol hemihydrate: redetermination of the crystal structure by neutron powder diffraction, Hirshfeld surface analysis and characterization of the thermal expansion.

Phenol hemihydrate, CHOH·0.5HO, crystallizes in the space group , = 8. The previously published crystal structure [CSD refcode PHOLHH; Meuthen & von Stackelberg (1960 ▸).

Cubic ice Ic without stacking defects obtained from ice XVII.

Amongst the more than 18 different forms of water ice, only the common hexagonal phase and the cubic phase are present in nature on Earth. Nonetheless, it is now widely recognized that all samples of 'cubic ice' discovered so far do not have a fully cubic crystal structure but instead are stacking-disordered forms of ice I (namely, ice Isd), which contain both hexagonal and cubic stacking sequences of hydrogen-bonded water molecules. Here, we describe a method to obtain large quantities of cubic ice Ic with high structural purity.

Nd,Ho-Codoped apatite-related NaLa(GeO)O phosphors for the near- and middle-infrared region.

The apatite-like NaLa9(GeO4)6O2:Nd3+,Ho3+ phosphor is prepared using the solid-state method. Rietveld refinement of high-resolution time-of-flight neutron powder diffraction measurements indicate that this compound crystallizes in the hexagonal system with space group P63/m, Z = 1 and unit cell parameters a = 9.88903(6) Å, c = 7.

Investigation of high-pressure planetary ices by cryo-recovery. II. High-pressure apparatus, examples and a new high-pressure phase of MgSO·5HO.

An apparatus is described for the compression of samples to ∼2 GPa at temperatures from 80 to 300 K, rapid chilling to 80 K whilst under load and subsequent recovery into liquid nitro-gen after the load is released. In this way, a variety of quenchable high-pressure phases of many materials may be preserved for examination outside the high-pressure sample environment, with the principal benefit being the ability to obtain high-resolution powder diffraction data for phase identification and structure solution. The use of this apparatus, in combination with a newly developed cold-loadable low-temperature stage for X-ray powder diffraction (the PheniX-FL), is illustrated using ice VI (a high-pressure polymorph of ordinary water ice that is thermodynamically stable only above ∼0.

Investigation of high-pressure planetary ices by cryo-recovery. I. An apparatus for X-ray powder diffraction from 40 to 315 K, allowing 'cold loading' of samples.

A low-temperature stage for X-ray powder diffraction in Bragg-Brentano reflection geometry is described. The temperature range covered is 40-315 K, with a temperature stability at the sample within ±0.1 K of the set point.

Accurate and precise lattice parameters of HO and DO ice Ih between 1.6 and 270 K from high-resolution time-of-flight neutron powder diffraction data.

Accurate and precise lattice parameters for DO and HO varieties of hexagonal ice (ice Ih, space group P6/mmc) have been obtained in the range 1.6 to 270 K. Precision of the lattice parameters (∼0.

Crossover between Tilt Families and Zero Area Thermal Expansion in Hybrid Prussian Blue Analogues.

Materials in the family of Prussian blue analogues (C H N ) K[M(CN) ], where C H N is the imidazolium ion and M=Fe, Co, undergo two phase transitions with temperature; at low temperatures the imidazolium cations have an ordered configuration (C2/c), while in the intermediate- and high-temperature phases (both previously reported as R3‾m ) they are dynamically disordered. We show from high-resolution powder neutron diffraction data that the high-temperature phase has zero area thermal expansion in the ab-plane. Supported by Landau theory and single-crystal X-ray diffraction data, we re-evaluate the space group symmetry of the intermediate-temperature phase to R3‾ .

Glycine zinc sulfate penta-hydrate: redetermination at 10 K from time-of-flight neutron Laue diffraction.

Single crystals of glycine zinc sulfate penta-hydrate [systematic name: hexa-aqua-zinc tetra-aquadiglycinezinc bis-(sulfate)], [Zn(HO)][Zn(CHNO)(HO)](SO), have been grown by isothermal evaporation from aqueous solution at room temperature and characterized by single-crystal neutron diffraction. The unit cell contains two unique ZnO octa-hedra on sites of symmetry -1 and two SO tetra-hedra with site symmetry 1; the octa-hedra comprise one [tetra-aqua-diglycine zinc] ion (centred on one Zn atom) and one [hexa-aqua-zinc] ion (centred on the other Zn atom); the glycine zwitterion, NHCHCOO, adopts a monodentate coordination to the first Zn atom. All other atoms sit on general positions of site symmetry 1.

X-ray and neutron powder diffraction analyses of Gly·MgSO4·5H2O and Gly·MgSO4·3H2O, and their deuterated counterparts.

We have identified a new compound in the glycine-MgSO4-water ternary system, namely glycine magnesium sulfate trihydrate (or Gly·MgSO4·3H2O) {systematic name: catena-poly[[tetraaquamagnesium(II)]-μ-glycine-κ(2)O:O'-[diaquabis(sulfato-κO)magnesium(II)]-μ-glycine-κ(2)O:O']; [Mg(SO4)(C2D5NO2)(D2O)3]n}, which can be grown from a supersaturated solution at ∼350 K and which may also be formed by heating the previously known glycine magnesium sulfate pentahydrate (or Gly·MgSO4·5H2O) {systematic name: hexaaquamagnesium(II) tetraaquadiglycinemagnesium(II) disulfate; [Mg(D2O)6][Mg(C2D5NO2)2(D2O)4](SO4)2} above ∼330 K in air. X-ray powder diffraction analysis reveals that the trihydrate phase is monoclinic (space group P21/n), with a unit-cell metric very similar to that of recently identified Gly·CoSO4·3H2O [Tepavitcharova et al. (2012).

Crystal structures of deuterated sodium molybdate dihydrate and sodium tungstate dihydrate from time-of-flight neutron powder diffraction.

Time-of-flight neutron powder diffraction data have been measured from ∼90 mol% deuterated isotopologues of Na2MoO4·2H2O and Na2WO4·2H2O at 295 K to a resolution of sin (θ)/λ = 0.77 Å(-1). The use of neutrons has allowed refinement of structural parameters with a precision that varies by a factor of two from the heaviest to the lightest atoms; this contrasts with the X-ray based refinements where precision may be > 20× poorer for O atoms in the presence of atoms such as Mo and W.

Crystal structures of spinel-type Na2MoO4 and Na2WO4 revisited using neutron powder diffraction.

Time-of-flight neutron powder diffraction data have been collected from Na2MoO4 and Na2WO4 to a resolution of sin (θ)/λ = 1.25 Å(-1), which is substanti-ally better than the previous analyses using Mo Kα X-rays, providing roughly triple the number of measured reflections with respect to the previous studies [Okada et al. (1974 ▶).

Structure of magnesium selenate enneahydrate, MgSeO4·9H2O, from 5 to 250 K using neutron time-of-flight Laue diffraction.

The complete structure of MgSeO4·9H2O has been refined from neutron single-crystal diffraction data obtained at 5, 100, 175 and 250 K. It is monoclinic, space group P2₁/c, Z = 4, with unit-cell parameters a = 7.222 (2), b = 10.

Structure, hydrogen bonding and thermal expansion of ammonium carbonate monohydrate.

We have determined the crystal structure of ammonium carbonate monohydrate, (NH4)2CO3·H2O, using Laue single-crystal diffraction methods with pulsed neutron radiation. The crystal is orthorhombic, space group Pnma (Z = 4), with unit-cell dimensions a = 12.047 (3), b = 4.