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[en] Core-level photoemission is often employed to extract chemical information concerning the atomic site and this requires assumptions concerning the balance between initial-state chemical and final-state screening effects. With this in mind, we have calculated the binding energy of the 4f level in gold metal using local-density total-energy calculations. We find a binding energy of 83.7 eV in good agreement with the experimental value of 83.9 eV. We are thus able to test several less complete computational schemes. For example, confining the response to a single site yields 84.3 eV, an error of 0.6 eV, while limiting the screening to the atom and its near neighbors produces an error of 0.07 eV. In additions, we have calculated the heat of solution of mercury in gold. This may be related via a Born-Haber cycle to the core-level binding energy assuming local screening and the equivalent core approximation. This yields a binding-energy error of 0.15 eV, which, while small, is of significance. Finally, we have explicitly decomposed the binding energy into initial- and final-state contributions and find a relaxation energy in gold of 17.7 eV compared to 13.1 eV for the isolated atom

[en] Molar enthalpies of solution of RbNO₃ in water at 298.15 K were measured in an LKB calorimeter. The molar enthalpies of solution extrapolated to infinite solution are: (36788 +- 30)J. mol^-1 (Alfa) and (36539 +- 52)J.mol^-1 (Aldrich). (author)

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[en] The enthalpy of solution of Tc₂O₇(c) in distilled water was measured using an LKB 8700-1 solution reaction calorimeter. The value obtained is ΔHsub(soln)⁰(Tc₂O₇, c, 298.15 K) = -(45.80 +- 1.21)kJ mol^-1. The enthalpies of solution of Tc₂O₇(c), Hg(l), Tc(c), and HgO(c), in an aqueous perchloric acid + ceric perchlorate solvent were also measured. These results were combined with the standard enthalpy of formation of HgO(c) from the literature to obtain the standard enthalpy of formation of Tc₂O₇(c). The key result of these measurements is ΔHsub(f)⁰(Tc₂O₇, c, 298.15 K) = (1127.6 +- 7.7) kJ mol^-1. (author)

[en] The interaction of a proton with an aluminum host is treated within the spherical model of a solid. Our results give for the heat of solution and activation energy of H in Al 0.593 and 0.5 eV, respectively, compared with the experimental values of 0.66 and 0.52 eV. The previously untreated nonspherical corrections are also estimated and shown to be small

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