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The Dissociation Energy of the Tetrasulfide Linkage
ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTThe Dissociation Energy of the Tetrasulfide LinkageI. Kende, T. L. Pickering, and A. V. TobolskyCite this: J. Am. Chem. Soc. 1965, 87, 24, 5582–5586Publication Date (Print):December 1, 1965Publication History Published online1 May 2002Published inissue 1 December 1965https:/…
Viscosity and Density of Boron Trioxide
Extensive and accurate viscosity values for molten B 2 O 3 are reported over the continuous range from 20 poises (at 1400°C) to 10 10 poises (at 318°C). The measurements were made with a wide‐range rotating‐cylinder viscometer. The melts were pretreated by bubbling superdry nitrogen through them to ensure a minimum wa…
Theory of Hyper-Raman Effects (Nonlinear Inelastic Light Scattering): Selection Rules and Depolarization Ratios for the Second-Order Polarizability
The symmetry properties of the third-rank tensor β which comprises the set of coefficients of quadratic terms in the expansion of the induced-dipole moment in the electric field are investigated, and the various linear combinations belonging to the irreducible representations are tabulated for the important molecular…
CHROMIAN SPINEL AS A PETROGENETIC INDICATOR: PART 1. THEORY
Previous investigators have shown that natural chromium-bearing spinel solid solutions adhere closely to the general formula (Mg, Fe ++ ) (Cr, Al, Fe +++ ) 2 O 4 and may therefore be graphically portrayed in a triangular prism, the length of which represents the ratios MgO/FeO, and the cross section the relative propo…
Magnetic-Field Dependence of the Rf Skin Depth of Gallium
The variation with magnetic field of the surface reactance of gallium single crystals at 2 Mc/sec has been investigated at helium temperatures and for fields up to 1500 G. The changes observed in the surface reactance depend in a very complicated way upon magnetic field, and correspond to variations of nearly 100% in…
Scattering of Long-Wavelength Phonons by Point Imperfections in Crystals
At very low temperatures the thermal conductivity of insulating crystals containing point defects is limited by boundary relaxation processes and by Rayleigh scattering of long-wavelength phonons: at higher temperatures resonant modifications of Rayleigh scattering and phonon-phonon scattering dominate. Experiments by…
Electron-Phonon Interaction in Organic Molecular Crystals
A theory of acoustic-mode scattering has been formulated within the tight-binding approximation of band theory, and has been applied to narrow-band semiconduction in organic molecular crystals. The latter problem has been treated previously only in terms of phenomenological scattering parameters. The interaction const…
Magnetic and Thermal Properties of [Cr3(CH3COO)6(OH)2]Cl·8H2O, a System of Clusters of ThreeCr3+Ions
The paramagnetic susceptibility and magnetic specific heat of the complex salt [${\mathrm{Cr}}_{3}$${(\mathrm{C}{\mathrm{H}}_{3}\mathrm{C}\mathrm{O}\mathrm{O})}_{6}$ ${(\mathrm{OH})}_{2}$]-Cl\ifmmode\cdot\else\textperiodcentered\fi{}8${\mathrm{H}}_{2}$O are examined theoretically in the light of recently obtained know…
Differential Cross Section for Trident Production
This paper discusses the differential cross section for pair production by electron scattering off an arbitrary fixed potential (trident). This cross section assumes that the three outcoming electrons' energies are to be measured. A modified version of the Monte Carlo procedures is used to obtain the cross section. Th…
The nuclear magnetic resonance spectrum of a cobyrinic acid derivative
Abstract In an extension of studies on the exchange of meso-hydrogen in porphyrins and reduced porphyrins (R. Bonnett & G.F. Stephenson, unpublished results) the nuclear magnetic resonance spectra of natural corrinoid derivatives have been investigated. Since it was hoped to observe a signal due to the CIO proton…
Synthesis of corroles and related ring systems
Abstract Corroles have been prepared by the irradiation of basic solutions of 1,19-dideoxybiladienes-ac. Some physical and chemical properties of corroles are described including the formation of the aromatic corrole anions. Cyclization of the nickel derivative of a 1,19 dimethyl-1,19- dideoxybiladiene-ac gives a macr…
Structure analysis of nickel(II)-1,8,8,13,13-pentamethyl- 5-cyano- trans -corrin chloride
Abstract This paper is a report on the structure determination by X-ray analysis of the nickel(II)-1,8,8,13,13-pentamethyl-5-cyano-trans-corrin chloride, the synthesis of which is described by Eschenmoser et al. in the preceding paper. There are two reasons that led us to carry out this work. In the first place, it wa…
Synthetic corrin complexes
Abstract In 1963 a description of the work in progress at the laboratories of the E.T.H. towards the synthesis of corrins was presented (Eschenmoser 1963). At that time, we were able to report the synthesis of the analytically and spectroscopically well defined crystalline nickel complex I; however, the ultimate probl…
Excitation of Plasma Waves Near Cyclotron Resonance in Potassium
Received 18 October 1965DOI:https://doi.org/10.1103/PhysRevLett.15.784©1965 American Physical Society
Acceptor-Impurity Infrared Absorption in Semiconducting Synthetic Diamond
The infrared-absorption spectra of a selection of aluminum-doped and nominally boron-doped semiconducting synthetic diamonds have been measured from 1 to 10 \ensuremath{\mu} at temperatures near 100\ifmmode^\circ\else\textdegree\fi{} and 300\ifmmode^\circ\else\textdegree\fi{}K. These spectra are shown to be very simil…
NMR Studies of Some Liquid Crystal Systems
Alignment by electric or magnetic fields of molecules comprising the liquid crystalline phase of a nematogenic material is manifested in proton magnetic resonance spectroscopy by the appearance of nuclear dipole-dipole fine structure. Additionally, much larger splittings ranging up to 300 G are observed in the deuteri…
Localized Atomic and Molecular Orbitals. II
Using a recently proposed procedure, the localized molecular orbitals are determined for minimal-basis-set LCAO—SCF wavefunctions of the molecules LiH, BH, NH, FH, Li2, B2, Be2, N2, F2, CO, BF, LiF. In all cases, well-defined inner-shell, lone-pair, and bond orbitals are found. They exhibit a considerable degree of tr…
Space Charge in Ionic Crystals. I. General Approach with Application to NaCl
The defect distribution in an ionic crystal is calculated for both pure crystals and crystals containing divalent cationic impurities. By taking the electrostatic energy into account explicitly, it is shown that bulk electrical neutrality and space-charge regions surrounding the vacancy sources are an inherent aspect…
Nuclear-Magnetic-Resonance Line Narrowing by a Rotating rf Field
A nuclear-magnetic-resonance method is explored, which effectively attenuates the dipolar interaction in solids. The experimental technique corresponds to the observation of a free-induction decay in a frame of reference rotating with the frequency of an applied rf field. When the amplitude ${H}_{1}$ of this field is…