Hydrogen molecule, energy curves for

Figure 3.2 Potential energy curve for hydrogen molecule-ion...

Fig. 6.—Potential energy curves for hydrogen molecules. The electron-pair halide molecules. bond structures H F , etc., are...

Figure 14. Total energy curves for hydrogen molecule according...

As it is done in Figure 1.2.1 for molecular hydrogen, it is possible to construct potential energy curves for different molecules. If the molecules consist of several atoms, this becomes a very complicated problem, but the general shape of the potential energy curves remains similar to that for molecular hydrogen. 

This mechanism has been disputed,primarily because Clyne and Thompson assumed that no recombination barrier occurred on the a A" surface. A more recent theoretical study of the potential energy curves for the molecule demonstrates the existence of potential barriers for both the a A" and A" surfaces, but the predicted barriers are low enough, 3.7 kcal/mol and 7.8 kcal/mol, for hydrogen recombination to occur thermally.These Cl calculations of the potential energy surfaces, however, used SCF energy-optimized structures of the ground electronic state for all three of the low-lying curves. 

Kolos W and Wolniewicz L 1965 Potential energy curves for the X H. and Cn states of the hydrogen molecule J. Chem. Phys. 43 2429-41... 

It might be supposed that, since the potential energy curve for V2 is of a similar shape to that in Figure 6.38(a), if we excite the molecule with sufficiently high energy it will eventually dissociate, losing six hydrogen atoms in the process ... 

Curve 1 represents the total energy of the hydrogen molecule-ion as calculated by the first-order perturbation theory curve 2, the naive potential function obtained on neglecting the resonance phenomenon curve 3, the potential function for the antisymmetric eigenfunction, leading to elastic collision. 

Curve 1 shows the electronic energy of the hydrogen molecule neglecting interelectronic interaction (from Burrau s solution for the molecule-ion) curve 2, the electronic energy empirically corrected by Condon s method and curve 3, the total energy of the hydrogen molecule, calculated by Condon s method. 

Fig. 42—2.—Energy curves for the hydrogen molecule-ion (in units e2/2ao), calculated for undistorted hydrogen atom wave functions.

Fig. 6-3S. Potential energy curves for water adsorption on metal surface in the states of molecules and hydrozjd radicals c = energy r = reaction coordinate solid curve = adsorption as water molecules and as partially dissociated hydroxj4 and hydrogen radicals broken curve = adsorption of completely dissociated oxygen and hydrogen radicals.

Fig. 3.6 Binding energy curves for the hydrogen molecule (lower panel). HF and HL are the Hartree-Fock and Heitler-London predictions, whereas LDA and LSDA are those for local density and local spin density approximations respectively. The upper panel gives the local magnetic moment within the LSDA self-consistent calculations. (After Gunnarsson and Lundquist (1976).)...

Fig. 3.9 Left-hand panel The overlap / electrostatic , exchange-correlation and bond integral 2ssa contributions to the binding energy of the hydrogen molecule (where ssa = h). Right-hand panel The binding energy curve (full line) is the sum of the three contributions , 2ssa and (see text for details). (After Skinner and Pettifor (1991).)...

Fig. 3-4.—Calculated energy curves for the hydrogen halogenide molecules. The two dashed curves for each molecule represent extreme ionic and extreme covalent structures, and the two full curves represent the actual structures resulting from resonance between these extreme structures. The dashed curves for HI lie very close to the full curves.

The discussion of hydrogen fluoride in this paragraph is a little different from that in the first two editions of this book. In the first two editions the calculated energy curve for the extreme ionic structure was shown as falling below that for the normal covalent structure, and the conclusion was reached that the bond between the hydrogen atom and the fluorine atom in the molecule... 

Figure 1.2 Potential energy curves for the approach of a hydrogen molecule and of two hydrogen atoms to a metal surface E is the activation energy — AH is the heat of adsorption subscripts p and c are, respectively, physical adsorption and chemisorption.

Kolos W, Wolniewicz L (1966) Potential-energy curve for the B1 Ylt state °f (he hydrogen molecule. J Chem Phys 45 509-514... 

Occasionally, potential energy curves for bond stretching vibrations can be unusually flat as well. One special case is of particular importance in hydrogen-bonded complexes. At infinite intermolecular distance two states are possible in which the proton is either bound to molecule A or to molecule B. The two states are related by a proton transfer process ... 

Figure 2 Schematic potential energy curve for the hydrogen molecules with scale at bottom of the curve exaggerated to show relation between n = 0 vibrational energy levels of the four isotopic forms of the molecules. Note that molecules containing a heavy isotope are more stable (have higher dissociation energies) than molecules with a light isotope. Isotope fractionations between molecules are explained by differences in their zero-point energies...

Figure 2. Potential energy as a function of metal-hydrogen distance for hydrogen molecules (curve 1) and for hydrogen atoms (curve 2).

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