Proton interstitial

The situation is equivalent to the formation of H30+ ( proton interstitial ) and OH ( proton vacancy ) in water where the endothermic formation enthalpy of the water dissociation reaction is also compensated by the gain of configuration entropy [61]. In both cases, defect chemical reactions can be formulated the dissociation reaction in water... 

Such ordered oxyhydroxides may form thermal defect pairs of proton vacancies and proton interstitials ... 

The close correspondence between the properties of Mu in Si as determined by /u,SR and pLCR and those for the AA9 center produced by implanting hydrogen in silicon shows that Mu in silicon and the AA9 center are isostructural and in fact almost identical. They are neutral isolated bond-centered interstitials. Numerous theoretical studies support this conclusion. The observation of such similar centers for muonium and hydrogen supports the generalization that hydrogen analogs of many of the muonium centers exist. Of course, this assumes that the effects of the larger zero-point vibration of the muon relative to the proton do not make a major contribution to structural differences. The p-SR experiments, reinforced by theory, demonstrate that another structure also exists for muonium in silicon, called normal muonium or Mu. This structure is metastable and almost certainly is isolated neutral muonium at a tetrahedral interstitial site. 

Penicillins Proton pump inhibitors Chronic interstitial nephritis Cyclosporine Lithium Aristolochic acid Renal vasculitis, thrombosis, and cholesterol emboli ... 

An important point to note is that this the above reaction produces lactate, not lactic acid. Nonetheless, protons are produced in glycolysis but in another reaction (Appendix 6.5). Consequently, the two end-products are lactate plus protons, which can be described as lactic acid. Despite this discussion, it can be argued that lactate dehydrogenase is not the terminal reaction of glycolysis, since the lactate plus protons have to be transported out of the cell into the interstitial space. This requires a transporter protein, which transports both lactate and protons across the plasma membrane and out of the cell. 

At about this time, J. Frenkel published a most seminal theoretical paper [J. Frenkel (1926)]. He suggested that in a similar way as (neutral) water dissociates to a very small extent into protons and hydroxyl ions, a perfect lattice molecule of a crystal (such as AgBr, which crystallizes in the B1-structure) will dissociate its regular structure elements, AgAg, into silver ions which are activated to occupy vacant sites in the interstitial sublattice, V). (The notation is explained in the list of symbols.) They leave behind empty regular silver ion sites (silver vacancies) symbolized here by V Ag. This dissociation process can be represented in a more chemical language (Kroeger-Vink notation) in Eqn. (1.1)... 

Protonation of 21 yields H2Os,0C(CO)24 (5 7). The crystal structure of the dihydride has not been determined, but analysis of the vibrational spectrum of the cluster in the region associated with motion of the interstitial carbon atom has led to the conclusion that the symmetry of 21 is reduced on protonation, probably by protonation of the central Os6 octahedron (see Section VI,A) (57). Cluster 21 also reacts with iodine to yield sequentially [Osl0C(CO)24I]", 22, and Os.oCfCO), 23, the result of electrophilic attack by 1+ on the dianion [Eq. (16)] (55). 

Molecular reorientations at Bjerrum fault sites are responsible for the dielectric properties of ice. A second type of fault (proton jumps from one molecule to a neighbor) accounts for the electrical conductivity of ice, but cannot account for the high dielectric constant of ice. Further discussion of such ice faults is provided by Franks (1973), Franks and Reid (1973), Onsager and Runnels (1969), and Geil et al. (2005), who note that interstitial migration is a likely self-diffusion mechanism. 

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