Vibrational spectra of monothiocarbamates-II. IR and Raman spectra, vibrational assignment, conformational analysis and ab initio calculations of S-methyl-N, N-dimethylthiocarbamate

The layered oxides of vanadium and molybdenum have been studied for close to 40 years as possible cathode materials for lithium batteries or electrochromic systems. The highly distorted metal octahedra naturally lead to the formation of a wide range of layer structures, which can intercalate lithium levels exceeding 300 Ah/kg. They have found continuing success in medical devices, such as pacemakers, but many challenges remain in their application in long-lived rechargeable devices. Their high-energy storage capability remains an encouragement to researchers to resolve the stability concerns of vanadium dissolution and the tendency of lithium and vanadium to mix changing the crystal structure on cycling the lithium in and out. Nanomorphologies have enabled higher reactivities to be obtained for both vanadium and molybdenum oxides, and with the latter show promise for electrochromic displays.

Layered vanadium and molybdenum oxides: batteries and electrochromics

Micelles. Physical chemistry of surfactant association

The electrophoretic mobilities of multilamellar phosphatidylserine vesicles were measured in solutions containing monovalent cations, and the xi potentials, the electrostatic potentials at the hydrodynamic plane of shear, were calculated from the Helmholtz--Smoluchowski equation In the presence of 01 M lithium, sodium, ammonium, potassium, rubidium, cesium, tetraethylammonium, and tetramethylammonium chloride, the xi potentials were -60, -62, -72, -73, -77, -80, -82, and -91 mV, respectively Similar results were obtained with phosphatidylglycerol vesicles; different results were obtained with cardiolipin, phosphatidylinositol, and phosphatidic acid vesicles The phosphatidylserine results are interpreted in terms of the Stern equation, a combination of the Gouy equation from the theory of the diffuse double layer, the Boltzmann relation, and the Langmuir adsorption isotherm Evidence is presented that suggests the hydrodynamic plane of shear is 2 A from the surface of the membrane in solutions containing the alkali metal cations With this assumption, the intrinsic association constants of the above monovalent cations with phosphatidylserine are 08, 06, 017, 015, 008, 005, 003, and 0 M-1, respectively The validity of this approach was tested in two ways First, the xi potentials of vesicles formed from mixtures of phosphatidylserine and a zwitterionic lipid, phosphatidylcholine, were measured in solutions containing different concentrations of sodium All the data could be described by the Stern equation if the "relaxation" of the ionic atmosphere, which is predicted by classic electrostatic and hydrodynamic theory to occur at low salt concentrations and high potentials, was circumvented by using only large (diameter greater than 13 micrometers) vesicles for these measurements Second, the fluorescent probe 2-(p-toluidinyl)naphthalene-6-sulfonate was used to estimate the potential at the surface of phosphatidylserine and phosphatidylglycerol vesicles sonicated in 01 M NaCl Reasonable agreement with the predicted values of the surface potential was obtained

Adsorption of monovalent cations to bilayer membranes containing negative phospholipids.

Nuclear magnetic resonance (NMR) data from water nuclei (1H, 2H, and 17O) can provide much information about the state of water in heterogeneous systems. In the present work, we present a theoretical framework for the interpretation of such data and discuss the implications of the theory. Due to the local anisotropy in heterogeneous systems, it is necessary to consider two components of water motion: a fast anisotropic reorientation superposed on a more extensive slow motion. On the basis of the experimentally verified assumption that these motions occur on different time scales, we develop a ’’two‐step’’ model of relaxation, showing that both motions may give important contributions to the relaxation. We derive a simple expression for the relevant correlation function, valid for isotropic systems. Anisotropic systems are also treated, making use of a new symmetry theorem for time correlation functions. The proof of this theorem is given in an Appendix. The magnitudes of the water 2H and 17O quadrupole coupling constants are estimated to 0.222 and 6.67 MHz, respectively. Results of ab initio quantum chemical calculations are presented, demonstrating the insensitivity of the water 17O field gradient to nearby ionic species. The possibilities and limitations of the NMR technique in answering the fundamental questions about water structure and dynamics in heterogeneous systems are discussed. We suggest a novel interpretation of the well‐known invariance of the ratio of 1H and 2H splittings. Furthermore, we argue that the available NMR data are consistent with a short‐ranged (≲2 molecular layers) perturbation of the water tumbling rate and anisotropy.

Interpretation of magnetic resonance data from water nuclei in heterogeneous systems

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Procedure and Computer Programs for the Structure Determination of Gaseous Molecules from Electron Diffraction Data.

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A Refinement of the Crystal Structure of V6O13.

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Compounds with the Marcasite Type Crystal Structure. IV. The Crystal Structure of FeSb2.

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Development of Compositional Heterogeneity in Alginate Degraded in Homogeneous Solution.

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Gunner Borch

Papers

Procedure and Computer Programs for the Structure Determination of Gaseous Molecules from Electron Diffraction Data.

A Refinement of the Crystal Structure of V6O13.

Compounds with the Marcasite Type Crystal Structure. IV. The Crystal Structure of FeSb2.

Development of Compositional Heterogeneity in Alginate Degraded in Homogeneous Solution.

Harmonic Force Fields for Some Heterocyclic Five-Membered Ring Molecules.