Adiabatic and postadiabatic channel description of atom–diatom long‐range half‐collision dynamics: Interchannel radial coupling for P1and P2anisotropy

Electronic nonadiabatic effects in low temperature radical-radical reactions. I. C(3P) + OH(2Π)

The formation of collision complexes, as a first step towards reaction, in collisions between two open-electronic shell radicals is treated within an adiabatic channel approach. Adiabatic channel potentials are constructed on the basis of asymptotic electrostatic, induction, dispersion, and exchange interactions, accounting for spin-orbit coupling within the multitude of electronic states arising from the separated reactants. Suitable coupling schemes (such as rotational + electronic) are designed to secure maximum adiabaticity of the channels. The reaction between C((3)P) and OH((2)Π) is treated as a representative example. The results show that the low temperature association rate coefficients in general cannot be represented by results obtained with a single (generally the lowest) potential energy surface of the adduct, asymptotically reaching the lowest fine-structure states of the reactants, and a factor accounting for the thermal population of the latter states. Instead, the influence of non-Born-Oppenheimer couplings within the multitude of electronic states arising during the encounter markedly increases the capture rates. This effect extends up to temperatures of several hundred K.

On the sudden Limit in the Capture of Particles for Long-Range Anisotropic Interactions

The capture cross sections and rigidity factors for atom-linear rotor anisotropic interaction proportional to

Correlation of Adiabatic States between Perturbed Rotor and Renner-Teller Limits for a Closed-Shell Ion + Open Shell Diatom System

The adiabatic channel interaction potentials for a system charge + dipole-open-shell-quadrupole linear rotor are calculated in the perturbed rotor and slightly anharmonic Renner-Teller limits. In both cases, first order charge-dipole and charge-quadrupole interactions are not additive; this leads to novel expressions for the energy levels. The result can be used in the construction of the adiabatic correlation diagrams between free rotor states with account for the