Hydrogen and deuteron

Protonic diffusion in ice has been investigated by a spectroscopic method. This method is based on the isotope effect on molecular vibrations. The mass difference between hydrogen and deuteron results in a frequency difference by a factor of V2 for the stretch mode. The peak positions are well separated in the spectra and hence their heights are converted to the H(D) concentrations with good accuracy. The diffusion process is monitored by measuring the reflection spectra of an H2O/ D2O ice bilayer, for which the equation of diffusion is described in analytical form. The H/D mutual diffusion coefficient measured at 400 K shows a monotonic decrease by two orders of magnitude as the pressure increases from 8 to 63 GPa. 

As in the case of hydrogen and tritium, deuterium exhibits nuclear spin isomerism (see Magnetic spin resonance) (14). However, the spin of the deuteron [12597-73-8] is 1 instead of S as in the case of hydrogen and tritium. As a consequence, and in contrast to hydrogen, the ortho form of deuterium is more stable than the para form at low temperatures, and at normal temperatures the ratio of ortho- to para-deuterium is 2 1 in contrast to the 3 1 ratio for hydrogen. 

Table V summarizes all the sharp absorptions due to local modes of vibration in proton and deuteron implanted GaP, GaAs and InP. It has to be noted that the results depend upon the reports. For instance, for GaP implanted with protons, Newman and Woodhead (1980) observed only one line at 1849 cm-1 whereas Sobotta et al. (1981) observed only one line at 2204 cm-1. These differences probably come from the differences in implantation conditions. However, unfortunately, these conditions are not always well described in the literature the ion energy and dose are usually given, but the ion current is specified only by Tatarkiewicz et al. (1987, 1988). This parameter is of importance as it contributes to control local temperature and therefore the defect creation and the binding of hydrogen to the lattice. 

Neutron diffraction involves bombarding a solid sample with neutrons to reveal proton and deuteron locations unavailable from X-ray crystallographic analyses. One can place H and D atoms within a structure—for instance, to identify hydrogen bonding of distal histidines to bound O2 in Mb and Hb.23... 

The second isotope effect, 87 , requires the proton and deuteron to be accurately located. The distance between the equilibrium positions of the potential energy well of double minima, symmetrical hydrogen bonds, which Ichikawa calls 7 h/h defined as q — 2i o . This distance can... 

Proton and deuteron relaxation show that relatively slow hydrogen exchange occurs in neutral solutions. The exchange is, however, acid catalyzed. Rivkind interpreted increased spin-spin relaxation rate with increasing acidity as due to protonated vanadyl and estimated... 

The first two equations represent the fact that the D-D reaction can follow either of two paths, producing tritium and one proton or hehum-3 and one neutron, with equal probability. The products of the first two reactions form the fuel for the third and fourth reactions and are burned with additional deuterium. The net reaction consists of the conversion of six deuterium nuclei lnlo two helium nuclei, two hydrogen nuclei, and two neutrons along with a net energy release of 43.1 MeV. The reaction products—helium, hydrogen, and neutrons—are harmless as contrasted with the myriad fission products obtained in a fission reactor. The neutrons produced may be absorbed in sodium to produce an additional 0.25 MeV per cycle. Therefore, the D-D reaction produces at least 7 MeV per deuterium atom (deuteron) and, with absorption in sodium, more than 10 MeV per fuel atom. 

Early workers in the field of H20-D20 systems recognized that it was possible to define different acidity constants for the isotopic hydrogen ions, that for an isotopically mixed ion it was necessary to distinguish between proton acidity and deuteron acidity and that it... 

Abstract. We consider the hyperfine structure of the Is and 2s states in muonic hydrogen and muonic deuterium. We put emphasis on two particular topics a possibility to measure the hfs interval in the ground state and a calculation of a specific difference. Ehfs(ls) — 8 Ehfa(2s). Such a measurement and the calculations are of interest in connection with an upcoming experiment at PSI in which different 2s — 2p transitions in muonic hydrogen shall be determined. Together all these investigations will improve the knowledge of the internal structure of proton and deuteron. 

The results of the first round of hydrogen and deuterium experiments mandated new and better experiments. The proton and the deuteron are, respectively, nature s simplest nucleus and compound nucleus thus, they are of enormous significance to a thor-... 

The objective of the 1938 experiments was to measure the magnetic moments of the hydrogen and deuterium nuclei as accurately as possible. In 1938, however, a new sense of promise inspired the members of Rabi s group as they prepared to apply the new resonance method to the hydrogens and to measure the magnetic moments of the proton and the deuteron to a new level of precision. Eventually, this objective was accompHshed successfully, but not without surprises that led to new basic knowledge about the atomic nucleus. 

Fenn, M. D., and Spinner, E., Proton and deuteron magnetic resonances of the strongly hydrogen-bonded complexes (HC02)H and(HC02)D " in aqueous solution. The primary isotope effect on chemical shift, and isotopic fractionation of labile hydrogen in H D mixtures, J. Phys. Chem. 88, 3993-3997 (1984). 

Complete conversion of protons into He was not possible, because of the lack of neutrons which in the free state decay to protons. After about 250 s, the mass of the universe consisted of about 75% hydrogen (protons and deuterons in a ratio of about 10 1), about 25% helium (" He and He in a ratio of about 10" 1) and traces of Li formed by reactions such as... 

Proton and deuteron nuclear magnetic resonance techniques are applied in solid hydrate research both for determining the hydrogen positions and for studying the dynamic processes of the water molecules ". ... 

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