Hydrogenation molecular

Neuhauser D, Baer M, Judson R S and Kouri D J 1989 Time-dependent three-dimensional body frame quantal wavepacket treatment of the atomic hydrogen + molecular hydrogen exchange reaction on the Liu-Siegbahn-Truhlar-Horowitz (LSTH) surfaced. Chem. Phys. 90 5882... 

Ortho-Para Tritium. As in the case of molecular hydrogen, molecular tritium exhibits nuclear spin isomerism. The spin of the tritium nucleus is S, the same as that for the hydrogen nucleus, and therefore H2 and T2 obey the same nuclear isomeric statistics (16). Below 5 K, molecular tritium is... 

Isotopic Exchange Reactions. Exchange reactions between the isotopes of hydrogen are well known and well substantiated. The equihbrium constants for exchange between the various hydrogen molecular species have been documented (18). Kinetics of the radiation-induced exchange reactions of hydrogen, deuterium, and tritium have been critically and authoritatively reviewed (31). The reaction T2 + H2 — 2HT equiUbrates at room temperature even without a catalyst (30). 

Concentration by gas chromatography has also been demonstrated. Elution chromatography has been used on an activated alumina column to resolve the molecular species H2, HT, and T2, thereby indicating a technique for separation or concentration of tritium (54). This method was extended (55) to include deuterium components. The technique was first demonstrated in 1964 using macro quantities of all six hydrogen molecular species (56). 

Table 3.2 Historically significant calculations for the electronic ground state of the hydrogen molecular ion...

See also Einstein, Albert Hydrogen Molecular Energy Nuclear Energy Nuclear Fission Nuclear Fusion Thermodynamics Units of Energy. 

The hydrogen molecular ion is rapidly (within a day at a standard gas density n of 104 cm-3) converted to H3 via the well-studied reaction ... 

In neutral or alkaline solution the conditions are altered so as to favour the immediate precursor of the final product of hydrogenation, namely, phenylhydroxylamine. This compound is obtained from nitrobenzene, suspended in ammonium chloride solution, by reduction with zinc dust. Zinc dust can decompose water with the formation of Zn(0H)2 if a substance is present which takes up the liberated hydrogen. Molecular, i e. ordinary, oxygen is capable of doing this and is thereby converted into hydrogen peroxide (M. Traube) ... 

In quantum mechanics, as we have already seen, one can approximately describe the hydrogen molecular ion as consisting of Ha+ and Hb, or Hb+ and Ha. Some combination of wave functions representing these two configurations is needed as an approximation of the actual state of affairs. The state of H2+ can then be thought of as a resonance hybrid of the two. 

In order to answer these questions, accurate experimental and theoretical results were needed for representative molecular systems. Theoreticians, for obvious reasons, have favored very simple systems, such as the hydrogen molecular ion (Hj) for their calculations. However, with only one electron, this system did not provide a proper test case for the molecular quantum mechanical methods due to the absence of the electron correlation. Therefore, the two-electron hydrogen molecule has served as the system on which the fundamental laws of quantum mechanics have been first tested. 

Figure 5.2 The six basic hydrogen storage methods and phenomena. From top left to bottom right compressed gas (molecular H2) liquid hydrogen (molecular H2) physisorption (molecular H2) on materials,forexample, carbon with a very large specific surface area hydrogen (atomic H) intercalation in host metals,...

Fig. 7.1. Three regimes of interaction in the hydrogen molecular ion. (a) At large distances, R>16 a.u., the. system can be considered as a neutral hydrogen atom plus a proton. The polarization of the hydrogen atom due to the field of the proton generates a van der Waals force, (b) At intermediate distances, 16>/ >4 a.u. the electron can tunnel to the vicinity of another proton, and vice versa. A resonance force is generated, which is either attractive or repulsive, (c) At short distances, R<4 a.u., proton-proton repulsion becomes important. (Reproduced from Chen, 1991c, with permission.)...

In the following, we present a treatment of the hydrogen molecular ion problem using a time-dependent Schrddinger equation ... 

Fig. 7.4. Wavefunctions of the hydrogen molecular ion. (a) The exact wavefunctions of the hydrogen molecular ion. The two lowest states are shown. The two exact solutions can be considered as symmetric and antisymmetric linear combinations of the solutions of the left-hand-side and right-hand-side problems, (b) and (c), defined by potential curves in Fig. 7.3. For brevity, the normalization constant is omitted. (Reproduced from Chen, 1991c, with permission.)...

In this subsection, we show that by evaluating the modified Bardeen integral, Eq. (7.14), with the distortion of the hydrogen wavefunction from another proton considered, as shown by Holstein (1955), an accurate analytic expression for the exact potential of the hydrogen molecular ion is obtained. 

---