Resonances atom-diatom reactions

Resonance energies. In Table I, the resonance energies for three collinear atom-diatom reactions are compiled. These include three resonances each for the H + FH and D + FD reactions and the lowest-energy resonance for H + H2 on the PK2 surface. All energies are relative to the minimum of the asymptotic reactant well. 

Table I. Resonance Energies (kcal/mol) for Three Collinear Atom-Diatom Reactions... 

Resonances in three-dimensional atom-diatom reactions... 

We present in this subsection the TD treatment for calculating initial state-specific total reaction probabilities for the atom-diatom reaction, H + 02 - HO + O. This is a particularly important combustion reaction (86) and it presents a real challenge to theoretical calculations because the PES has a deep well of more than 2.3 eV which supports many bound states and narrow resonances. Much progress has been made in the past few years by Neuhauser et al. in TD calculation of atom-diatom reactive scattering... 

Potential energy surface and first resonance characteristics for the isotopic hydrogenic atom diatom reactions. ... 

G. C. Schatz and A. Kuppermann, An analysis of resonant and direct processes in collinear atom-diatom reactions, manuscript in preparation,... 

Gr Reactions. In a Gr reaction, the BO hole corresponds to a pair of radicals or a biradical. The separation of the bonding and antibonding MOs in a diatomic molecule is proportional to the resonance integral P between their two AOs (Section 1.5). This in turn is proportional to the extent to which they overlap in space (Section 1.5). As the atoms move apart, P will therefore decrease, becoming zero when the molecule has dissociated completely. In the limit of complete dissociation, the ground-state and excited-state surfaces for the molecule consequently coincide (Fig. 6.26). 

Quantum scattering calculations on the reactions of atoms with diatomic molecules for linear geometry have played a very useful role (for example, clearly demonstrating the importance of vibrational enhancement and resonances in such reactions, which still exist in three-dimensional studies ). Many three-atom reactions have minimum energy paths in the potential energy surface that are close to linear geometries, so... 

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