Lithium Deuteride Research Articles

Energy- and Particle-Confinement Properties of an End-Plugged, Linear, Theta Pinch

Experiments show that axial confinement of plasma in a straight theta-pinch solenoid is improved by placing solid lithium deuteride plugs at the ends. The energy confinement is increased nearly threefold in agreement with theoretical estimates which assume classical electron thermal conduction and no convective losses. The confinement of deuterium ions is explained by classical Coulomb collisions in the ablated lithium deuteride plasma.

A comment on 'Lattice dynamics of lithium hydride and lithium deuteride: effect of long-range three-body forces'

An error is pointed out in the discussion by Laplaze J. Phys. C, vol.10, p.3499 (1977) dealing with the results of one of the author's lattice dynamical models and Laplaze's results are briefly compared with those based on their model.

Lattice dynamics of lithium hydride and lithium deuteride: effect of long-range three-body forces

Some new experimental data (optical measurement and elastic constant determination) have shown discrepancies with model calculations, in LiH and LiD crystals. Using the classical shell model, the author has shown that second-neighbour H-H interactions are very important in this crystal. In order to correct the frequencies, particularly on the TO branches in the (1, 1, 1) direction, shell deformation effects have been introduced into the model and it has been shown that there exist no short-range forces able to improve the calculation. It is then necessary to introduce long-range three-body forces to explain all the dynamic properties of these two crystals.

Solutions of lithium salts in liquid lithium. The electrical resistivity of solutions of nitride, hydride and deuteride

The electrical resistivities, ρ, of solutions of lithium nitride, lithium hydride and lithium deuteride in liquid lithium have been determined for concentrations, x, up to 2.77, 5.68 and 2.22 mol % non-metal over the temperature ranges 200–450, 257–551 and 276–500°C, respectively. For each solute, resistivity increases linearly with increasing concentration, except for very dilute solutions, and the coefficient, dρ/dx increases with increasing temperature. Nitride causes the greatest increase in resistivity [dρ/dx= 7.0 × 10–8Ωm (mol % N)–1 at 400°C], and hydride and deuteride show no detectable isotope effect [dρ/dx= 4.9 × 10–8Ωm (mol % H or D)–1 at 400°C]. The resistivities of mixtures of nitride and hydride in lithium are additive, thereby showing lack of association between these solutes. Ammonia vapour reacts with the metal to form hydride and nitride which dissolve to increase the resistivity by their characteristic amounts.

Onium ions. XVI. Hydrogen-deuterium exchange accompanying the cleavage of ammonium (tetradeuterioammonium) trifluoroacetate by lithium deuteride (hydride) indicating SN2 like nucleophilic displacement at quaternary nitrogen through pentacoordinated ammonium hydride

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTOnium ions. XVI. Hydrogen-deuterium exchange accompanying the cleavage of ammonium (tetradeuterioammonium) trifluoroacetate by lithium deuteride (hydride) indicating SN2 like nucleophilic displacement at quaternary nitrogen through pentacoordinated ammonium hydrideGeorge A. Olah, Daniel J. Donovan, Jacob Shen, and Gilles KlopmanCite this: J. Am. Chem. Soc. 1975, 97, 12, 3559–3561Publication Date (Print):June 1, 1975Publication History Published online1 May 2002Published inissue 1 June 1975https://doi.org/10.1021/ja00845a069RIGHTS & PERMISSIONSArticle Views135Altmetric-Citations19LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InReddit PDF (397 KB) Get e-Alerts Get e-Alerts

Target fabrication and positioning techniques for laser fusion experiments

Solid targets of pure deuterium or deuterium-bearing compounds are required for experiments designed to explore the feasibility of laser fusion as a source of energy. This paper deals with three aspects of the targets used in this application, namely, (i) the selection of suitable compounds which provide optimum heating by the laser radiation, (ii) the fabrication of appropriately sized and shaped targets from these compounds, and (iii) the positioning of these targets in laser-irradiation experiments. Spherical targets of lithium deuteride, deuterated polyethylene, and paraffins with diameters of 50–200 μ are considered, as well as 400 μ cylindrical extrusions of deuterium ice. Detailed descriptions are given of the apparatus and techniques used to position these targets in the focal region of the laser radiation.

1387. Investigations of plasma generated at action of laser beam on target of lithium deuteride: G G Dolgov-Savelev and V N Karnyushin, Diagnostics of Plasma, Coll, No 3, Atomizdat Moscow 1973, 172–177 ( in Russian)

1387. Investigations of plasma generated at action of laser beam on target of lithium deuteride: G G Dolgov-Savelev and V N Karnyushin, Diagnostics of Plasma, Coll, No 3, Atomizdat Moscow 1973, 172–177 ( in Russian)

Dispersion of phonons in lithium deuteride

The study of dispersion of phonons of lithium deuteride (LiD) has been presented on the basis of the three-body force shell model which includes the effect of charge transfer of about 0.88 electrons. The results show an excellent agreement with extensively measured phonon dispersion data.

The reaction of aluminium hydroborate with some ethers and amines, and with lithium hydride, deuteride, chloride, and hydroborate

Aluminium hydroborate reacts with isopropyl ether and tetrahydrofuran forming simple 1 : 1 complexes. With methylamine a 1 : 2 complex, Al(BH4)3,2MeNH2, is formed which is stable to 50°, while dimethylamine affords a 1 : 1 complex. The addition of excess of either of these amines results in hydrogen evolution, and both cleavage and degradation of the aluminium hydroborate occurs. The i.r. and n.m.r. spectroscopic properties of the complexes are reported, and a comparison is made of the reactivity of the ligands towards diborane and aluminium hydroborate. The interaction of aluminium hydroborate with anionic species (LiH, LiD, LiBH4, and LiCl) is also discussed.

Trapping of keV deuterons in lithium

Measurements have been made of the trapping of 18 keV deuterons in solid and liquid lithium targets over the temperature range 320-730 K. Trapping efficiencies of 97% were observed in the liquid for doses of more than 1019 ions/cm2 at temperatures up to 700 K. At higher temperatures the dissociation of lithium deuteride prevented further trapping. In the solid lithium the trapping efficiencies were in the range 70-95% but were rather irreproducible.

Role of focusing in heat-conduction heating of a plasma by high-power laser radiation

A theoretical analysis is given of the process of heating of a plasma by a spherical electron thermal wave generated by an ultrashort (10−11–10−12 sec) laser pulse incident on a solid target. Analytic expressions are obtained for the ion temperature, the volume, and the lifetime of a hot plasma. The neutron yield is calculated for a deuterium plasma and for a lithium deuteride plasma as a function of the absorbed energy and the area on which the laser radiation is focused.

Investigations of a plasma formed by ultrashort laser pulses

Experimental investigations were made of the processes occurring during the high-temperature heating of plasma by ultrashort laser pulses focused onto the surface of lithium deuteride. The following methods were used in these experiments: schlieren photography of a plasma illuminated with ultrashort pulses; photography of an expanding plasma with an image converter; investigation of the time dependences of the reflection of laser pulses; determination of the electron temperature of a plasma from its x-ray emission. The principal processes which accompany the heating of a plasma by ultrashort pulses are considered theoretically within the framework of approximations based on experimental results.

Observation of Neutrons Produced by Laser Irradiation of Lithium Deuteride

The observation of neutrons produced by irradiation of polycrystalline LiD targets with a high-power laser is reported. Single pulses from a mode-locked ${\mathrm{Nd}}^{+3}$-doped glass laser were amplified up to energies of 25 J. Pulse widths were 2-3 psec as measured by the two-photon fluorescence technique. The analyses of these experiments yield a somewhat higher rate of neutron production than the similar experiments recently reported by Basov et al..

Experiments on the observation of neutron emission at a focus of high-power laser radiation on a lithium deuteride surface

Theoretical calculations indicate that laser radiation may be used to heat a deuterium plasma to temperatures at which thermonuclear neutron emission may be observed. Using a neodymium glass laser, producing a 20-joule pulse of approximately 10-11-second pulse length, preliminary evidence of neutron emission has been obtained.

Procedure for the preparation of low-boiling alcohols and amines via lithium aluminum hydride and deuteride reduction

Procedure for the preparation of low-boiling alcohols and amines via lithium aluminum hydride and deuteride reduction

Syntheses of the alkali metal borodeuterides

A synthesis of sodium borodeuteride on a molar scale has been developed. Trimethylamineborane was exchanged (6) with deuteriosulfuric acid in deuterium oxide to obtain trimethylamineborane-d3 of a high isotopic purity. Reaction of trimethylamineborane-d3 with sodium methoxide in diglyme at 120–150 °C yielded sodium borodeuteride, which, after purification, was obtained in a 40–50% overall yield. The conditions for obtaining material of a high isotopic and chemical purity were found to be rather stringent but, once worked out, were easily reproducible.Lithium borodeuteride and potassium borodeuteride were also prepared from trimethylamineborane-d3 and the corresponding methoxide salts. An alternative synthesis of lithium borodeuteride, involving the reaction between lithium deuteride and boron trifluoride etherate, was found to be more satisfactory, since it avoided the formation of stable 1:1 solvent complexes with lithium borodeuteride.The products that were obtained had a chemical purity of 97%, and contained 98–99 atom % deuterium. The deuterium analyses were performed by reducing a series of ketones containing no α hydrogens and analyzing the secondary alcohol by nuclear magnetic resonance for residual hydrogen on the alcohol carbon.

Infrared lattice vibrations of single crystal lithium hydride and some of its isotopic derivations

The infrared reflection spectra of single crystal lithium hydride, lithium deuteride, lithium-6 hydride, and lithium-7 hydride have been measured and analyzed. The long wavelength limits of the optical lattice vibrational frequencies have been determined and used to find the static dielectric constants and Szigeti effective charges of all the isotopic variations studied. It is found that the square of the longitudinal (or transverse) frequency is inversely proportional to the reduced mass of the ion pairs forming the crystal. The Szigeti effective charge for LiH, e s ∗ = (0.53±0.02)e , is qualitatively accounted for by the Dick and Overhauser shell model for the vibrating ions. A slight isotope effect on the e s ∗ is noted in LiD and the difference in effective charges is interpretable within the framework of the shell model.

Rotational Magnetic Moments of Lithium Hydride and Deuteride

Resonances of the rotational magnetic moments were observed in molecular beams of lithium hydride and lithium deuteride. The shape of the LiH rotational magnetic resonance curve was observed to be asymmetric and width of the curve was observed to increase with increasing magnetic field. These effects were ascribed to centrifugal stretching causing the magnetic moment per unit of angular momentum to vary with angular momentum. The variation was assumed to be of the form, /sub R//J = g/sub 0/ + CJ(J + 1), where /sub R/ is the rotational magnetic moment and J is the quantuim number of the total rotational angular momentum. The values of the constants g/sub 0/ and C assigned to LiH were: g/sub 0/ = -0.654 450 deg C in a 0.007 nuclear magneton and C (1.2 450 deg C in a 0.6) x 10/sup -4/ nuclear magneton. For LiD, these constants were found to be: g/ sub 0/ = -0.272 450 deg C in a 0.005 nuclear magneton and C = (3.4 450 deg C in a 1.7) x 10/sup -5/ nuclear magneton. The electric dipole moment and its polarity were calculated from the rotational magnetic moments of LiH and LiD. The results of thismore » calculation were /sub e/ = 5.9 450 deg C in a 0.5 debyes with the polarity Li/sup +/H/sup -/. The magnitude of the rotational magnetic moment resonance signals suggest the occurrence of multiple-quantum transitions, which may make possible the observation of rotational magnetic moment resonances in other molecules, even if the rotational gyromagnetic ratios are quite small. (auth)« less

An investigation of the production of polarized neutron beams in the energy range 18 to 120 MeV

Abstract In a search for a polarized neutron beam, neutrons were produced by bombarding thick targets of lithium deuteride and aluminium with protons of 143 MeV. The polarization of the neutrons was investigated as a function of neutron energy between 18 and 120 MeV and at angles of neutron production of 25°, 35° and 45°. An aluminium target and production angle of 45° have been chosen for future work, the polarization of the resulting neutron beam varying from 0.135 ± 0.029 at 22.5 MeV to 0.308 ± 0.038 at 100 MeV.

The Radiative Capture of Protons by Neutrons at 50 MeV

By using an internal lithium deuteride target in the Harwell cyclotron, and `hardening' the resulting scattered neutrons with polythene, a low intensity beam of neutrons with an energy peak at 50 MeV was produced. This beam passed through a 9 cm hydrogen bubble chamber and produced in it reactions of the type n+p->d+γ which were distinguished by the range-angle distribution of the deuterons from the background of elastic n-p scatters. A cross section of 110±60 μbn was found for the process.