The gas-phase thermochemistry of TiH
نویسندگان
چکیده
The homolytic bond dissociation energy of the titanium neutral hydride D ‘(Ti-H) is determined experimentally for the first time by using guided ion beam tandem mass spectrometry to measure the kinetic energy dependence of the endothermic hydride abstraction reactions of Ti+ with methylamine, dimethylamine, and trimethylamine. From the thresholds of these reactions, the value of D ‘(Ti-H) = 2.12 f 0.09 eV (48.9 f 2.1 kcal/mol) at 298 K is derived. Other 298 K thermodynamic values obtained are D’(Ti+-H-) = 8.19 + 0.09 eV (188.8 f 2.1 kcal/mol), I.E.(TiH) = 6.59 f 0.14 eV, P.A.(Ti-) = 15.64 + 0.09 eV (360.6 f 2.1 kcal/mol), and AfH( TiH) = 116.4 f 2.3 kcal/mol. This thermochemistry is compared with theoretical values and its relationship to hydride bond energies for the other first row transition metals is discussed.
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