Karel Houfek

Dissociative electron attachment and vibrational excitation of CF3Cl: Effect of two vibrational modes revisited

We present a study of dissociative electron attachment and vibrational excitation processes in electron collisions with the

Interaction of O− and H2 at low temperatures

{\mathrm{CF}}_{3}\mathrm{Cl}

Collisions of electrons with hydrogen atoms II. Low-energy program using the method of the exterior complex scaling ✩

molecule. The calculations are based on the two-dimensional nuclear dynamics including the C-Cl symmetric stretch coordinate and the

Dissociative attachment of low-energy electrons to vibrationally excited hydrogen molecules

{\mathrm{CF}}_{3}

New version of hex-ecs, the B-spline implementation of exterior complex scaling method for solution of electron–hydrogen scattering

symmetric deformation (umbrella) coordinate. The complex potential energy surfaces are calculated using the ab initio

Reducing the dimensionality of grid based methods for electron-atom scattering calculations below ionization threshold

R

Recent developments in R-matrix applications to molecular processes

-matrix method. The results for dissociative attachment and vibrational excitation of the umbrella mode agree quite well with experiment whereas the cross section for excitation of the C-Cl symmetric stretch vibrations is about a factor-of-three too low in comparison with experimental data.

Comparison of the Chebyshev Method and the Generalized Crank-Nicholson Method for time Propagation in Quantum Mechanics

Reactive collisions between O(-) and H2 have been studied experimentally at temperatures ranging from 10 K to 300 K using a cryogenic radiofrequency 22-pole ion trap. The rate coefficients for associative detachment, leading to H2O + e(-), increase with decreasing temperature and reach a flat maximum of 1.8 × 10(-9) cm(3) s(-1) at temperatures between 20 K and 80 K. There, the overall reaction probability is in good agreement with a capture model indicating efficient non-adiabatic couplings between the entrance potential energy surfaces. Classical trajectory calculations on newly calculated potential energy surfaces as well as the topology of the conical intersection seam leading to the neutral surface corroborate this. The formation of OH(-) + H via hydrogen transfer, although occurring with a probability of a few percent only (about 5 × 10(-11) cm(3) s(-1) at temperatures 10-300 K), indicates that there are reaction paths, where electron detachment is avoided.

Efficient Numerical Solution of Time‐Dependent Multichannel One‐Dimensional or Radial Problems In Quantum Mechanics

a b s t r a c t While collisions of electrons with hydrogen atoms pose a well studied and in some sense closed problem, there is still no free computer code ready for ‘‘production use’’, that would enable applied researchers to generate necessary data for arbitrary impact energies and scattering transitions directly if absent in online scattering databases. This is the second article on the Hex program package, which describes a new computer code that is, with a little setup, capable of solving the scattering equations for energies ranging from a fraction of the ionization threshold to approximately 100 eV or more, depending on the available computational resources. The program implements the exterior complex scaling method in the B-spline basis.

Efficient Numerical Solution of Coupled Radial Differential Equations in Multichannel Scattering Problems

Dissociative electron attachment to hot hydrogen molecules is studied in the framework of nonlocal resonance model. The method based on the use of the Bateman approximation, well known in nuclear physics, is adapted for solving the Lippmann-Schwinger integral equation of the nonlocal resonance model and applied to the calculation of cross sections of inelastic resonant electron-molecule collisions. The proposed method is compared with the Schwinger-Lanczos algorithm used extensively for the treatment of these processes. It is shown that the Bateman approximation is very useful and efficient for treating the non-separable nonlocal potentials appearing in the integral kernels of the nonlocal resonance models. The calculated cross sections for the dissociative attachment of electrons to vibrationally excited hydrogen molecules are of importance for astrophysics.