Showing papers on "Lattice energy published in 1973"
TL;DR: In this paper, a model for the treatment of the motion of ions through crystallographic tunnels, as are found in materials that are interesting solid electrolytes, was developed for the consideration of both point charge and higher order attractive terms as well as overlap repulsion effects.
104 citations
TL;DR: Li2MnO3 as mentioned in this paper is a variant of the NaCl-type structure family and crystallizes monoclinic, a = 4.928 A, b = 8.533 A, c = 9.604 A, β = 99.5°, Z = 8; as a version of the Li2SnO3 type of structure.
Abstract: Li2MnO3 kristallisiert nach Guinier-Daten monoklin, a = 4,928 A, b = 8,533 A, c = 9,604 A, β = 99,5Deg;, Z = 8, in einer Variante des Li2SnO3-Typs. Parameter siehe Text. Unterhalb der Neel-Temperatur (≈50°K) liegt Antiferromagnetismus, oberhalb Paramagnetismus, μ = 3,83, μB, θ = −33°K (Curie-Weiss) vor. Der Madelung-Anteil der Gitterenergie, MAPLE, wird berechnet und diskutiert.
On the Knowledge of the NaCl-Type Structure Family: New Investigations on Li2MnO3
According to Guinier photographs Li2MnO3 crystallizes monoclinic, a = 4.928 A, b = 8.533 A, c = 9.604 A, β = 99.5°, Z = 8; as a variant of the Li2SnO3 type of structure. Parameters see text. Below the Neel temperature (≈50°K) we find antiferromagnetism, above paramagnetism with μ = 3.83 μB, θ = −33°K (Curie-Weiss Law). The Madelung Part of Lattice Energy, MAPLE, is calculated and discussed.
69 citations
TL;DR: In this article, the energy distribution of noble gas ions in the energy range below 1 keV from a single-crystalline surface depends on the composition and the structure of the surface, the mass and energy of the impinging ions and the geometrical conditions of the experiment.
64 citations
53 citations
TL;DR: In this article, a cubic anvil X-ray diffraction press has been developed, where powder diffraction patterns of substances subjected to quasi-hydrostatic pressure up to 100 kbar and temperature up to 1000°C can be satisfactorily obtained using a scintillation counter and an electronic counting system.
Abstract: A cubic anvil X-ray diffraction press has been developed. With this apparatus powder diffraction patterns of substances subjected to quasi-hydrostatic pressure up to 100 kbar and temperature up to 1000°C can be satisfactorily obtained using a scintillation counter and an electronic counting system for detecting diffracted X-rays. To show the capabilities of this apparatus, the effect of pressure on lattice parameters of KCl, which shows NaCl type to CsCl type structural phase transformation at high pressures has been determined up to 100 kbar and thermal expansion of high pressure phase of KCl has also been measured up to 800°C. Using these data. lattice energies of both phases of KCl at the transformation pressure are calculated with the revised Born model of ionic crystals.
33 citations
TL;DR: In this article, the lattice energies of these oxides were calculated from equations based on the Born model and containing terms accounting for van der Waals interactions, which yielded 149 ± 8 kcal/mole for the increase in enthalpy of the reaction of atomic oxygen with two electrons.
Abstract: The lattice energies of these crystals were calculated from equations based on the Born model and containing terms accounting for van der Waals interactions. The results were, in kilocalories per mole: MgO, −905; CaO, −815; SrO, −767; BaO, −736. These lattice energies, when combined with appropriate thermochemical data, yielded 149 ± 8 kcal/mole for the increase in enthalpy of the reaction of atomic oxygen with two electrons. This value is less than most values previously computed for this process. The decreased value is attributed to the higher, more accurate compressibilities used in evaluating the lattice energies of these oxides.
25 citations
TL;DR: In this article, the effects of the sublattice displacements on the lattice energy and on the $d$ electrons were investigated. But the model was adopted for the cubic and tetragonal phases of the optical phonon.
Abstract: We adopt the constant-density-of-states one-dimensional model for the $d$ bands but carefully include the effects of the sublattice displacements on the lattice energy and on the $d$ electrons. Then, we are able to explain quantitatively the behavior of various properties of ${\mathrm{Nb}}_{3}$Sn in both the cubic and tetragonal phases such as the shear modulus, the spontaneous tetragonal strain, and sublattice shift, with a reasonable set of parameters (e.g., density of states 3.2 states/eV atom, Fermi temperature 195 K). We deduce the energy of the ${\ensuremath{\Gamma}}_{12}$ optical phonon to be 21 meV.
17 citations
TL;DR: In this paper, the results of lattice dynamical calculations on solid chlorine and iodine are presented, and a consideration of the intermolecular forces has shown that a charge transfer interaction is important, as well as Lennard-Jones and quadrupole interactions.
14 citations
TL;DR: In this article, a 50 cm bent-quartz crystal vacuum spectrograph was used to obtain the chlorine K absorption spectra of PdCl2, CdCl 2, and FeCl3 for the first transition metal dichlorides.
Abstract: The chlorine K absorption spectra of PdCl2, CdCl2, and FeCl3 have been obtained with a 50‐cm bent‐quartz‐crystal vacuum spectrograph. A prominent absorption maximum has been detected at the threshold and is interpreted in terms of the electron transfer model. Results are evaluated by comparing the obtained spectra with the chlorine K absorption spectra of the first‐transition metal dichlorides reported previously. Chemical shifts are found for the first absorption band and discussed in relation to the ionization potentials of the metal ions and the lattice energy. The chlorine K absorption spectra of the chlorides are discussed in relation to the crystal structure.
13 citations
13 citations
TL;DR: In this article, the structure of Rb2TeCl6 has been determined by single crystal X-ray diffraction and refined to a final R of 0·050, which is sensitive to the assumed charge distributions within the anion.
Abstract: Using room temperature diffractometer intensity data the structure of Rb2TeCl6 has been determined by single crystal X-ray diffraction and refined to a final R of 0·050. The structure consists of regular octahedral [TeCl6]2–[Te–Cl = 2·541 A(corrected)]. Lattice energy calculations on the resulting structure (for various charge distributions within the anion) are reported and are found to be sensitive to the assumed charge distributions within the anion. The measured heats of solution of TeCl4 and Rb2TeCl6 in hydrochloric acid allow the standard heat of formation of Rb2TeCl6 to be calculated as –294·4 kcal mol–1 at 298 K. Using the calculated lattice energy, the enthalpy of reaction (i) is calculated to be –21·8 ± 17 kcal mol–1 at 298 K where the large error in the value is a reflection of the uncertainties in the charge distribution of the anion. 2Cl–(g)+ TeCl4(g)→[TeCl6]2–(g)(i) Thermochemical measurements on the analogous tin compounds gives the standard heat of formation of Rb2SnCl6 as –365·5 kcal mol–1 at 298 K, and, together with the lattice energy calculations, allow the enthalpy change for reaction (ii) to be estimated. 2Cl–(g)+ SnCl4(g)→[SnCl6]2–(g)(ii) As measured by the enthalpy of the gas phase reaction, the two Lewis acids SnCl4 and TeCl4 have, towards the chloride ion ligand, the same acceptor strength.
TL;DR: In this article, a cast film of poly-3-methyl-1-butene has been synthesized by Et2AlCl/tBuCl initiator at −130°C and three well defined crystalline phases, α, β and γ, characterized by infrared spectroscopy.
Abstract: Poly-3-methyl-1-butene has been synthesized by Et2AlCl/tBuCl initiator at −130°C. A cast film of this material gave three well defined crystalline phases, α, β, and γ, characterized by infrared spectroscopy. The γ polymorph could not be obtained independently of the other two. Synthesis and/or manipulative procedures that would consistently give only one of the polymorphs are still unavailable. Evidently, the three crystalline phases have very similar lattice energies, and the subtle factors that determine the ultimate nature of the crystal lattice are not yet understood.
01 Jan 1973
TL;DR: In this article, the authors studied stationary and time-resolved energy transfer from the Eu3+ (C3i) ions to the eu3+(C2) ions and the spectrum of Eu 3+ ion pairs at identical lattice sites.
Abstract: In Y2O3 the Eu3+ ions can occupy two different lattice sites with the site symmetries C3i and C2. We have studied stationary and time-resolved energy transfer from the Eu3+(C3i) ions to the Eu3+(C2) ions and the spectrum of Eu3+ ion pairs at identical lattice sites. The experimental results can be explained with a fixed range of interaction Ro ≈ 9 A between the Eu3+ ions. The results show some evidence for coherency effects in the energy transfer from Eu3+ (C3i) ions to Eu3+(C2) ions.
TL;DR: In this article, the values of the thermodynamic radii (rt) of borohydride and aluminum hydride ions were calculated using the Kapustinskii equation from the Born-Haber cycle.
Abstract: 1.
The values of the thermodynamic radii (rt) of borohydride and aluminum hydride ions were calculated.
2.
The crystal lattice energy of borohydrides and aluminum hydrides of IA and IIA were calculated on the basis of rt[ElH4−] according to the Kapustinskii equation, from the Born-Haber cycle; and by the method of comparative calculation.
3.
The energy of formation of RbAlH4, addition of (H−) to [AlH3], and other conversions was calculated on the basis of the energy of formation of the gaseous aluminum hydride ion.
4.
A correspondence was detected between the nature of the changes in the crystal lattice energy and certain properties of aluminum hydrides and borohydrides: the thermal stability, solubility, and ability for formation from the elementary substances.
TL;DR: A reinvestigation into the Lewis acidity of trialkoxyboranes B(OR)3 has shown that contrary to earlier reports none of these compounds forms Lewis acid-base adducts with nitrogen bases as mentioned in this paper.
Abstract: A reinvestigation into the Lewis acidity of trialkoxyboranes B(OR)3, has shown that contrary to earlier reports none of these compounds forms Lewis acid–base adducts with nitrogen bases. However they do form ‘onium’ salts in which the anion is a tetra-alkoxyborate complex. The thermodynamic stability of these salts is discussed and is shown to be critically dependent upon the crystal lattice energy and temperature. Triphenoxyborane forms the piperidine adduct and corresponding piperidinium salt.