Further generalization and numerical implementation of pseudo-time Schroedinger equations for quantum scattering calculations
| dc.creator | Mandelshtam, V. A. | |
| dc.creator | Neumaier, A. | |
| dc.date | 2002-04-17 | |
| dc.date.accessioned | 2026-07-07T05:47:28Z | |
| dc.date.available | 2026-07-07T05:47:28Z | |
| dc.description | We review and further develop the recently introduced numerical approach for scattering calculations based on a so called pseudo-time Schroedinger equation, which is in turn a modification of the damped Chebyshev polynomial expansion scheme. The method utilizes a special energy-dependent form for the absorbing potential in the time-independent Schroedinger equation, in which the complex energy spectrum E_k is mapped to u_k inside the unit disk, where u_k are the eigenvalues of some explicitly known sparse matrix U. Most importantly for the numerical implementation, all the physical eigenvalues u_k are extreme eigenvalues of U, which allows one to extract these eigenvalues very efficiently by harmonic inversion of a pseudo-time autocorrelation function using the filter diagonalization method. The computation of 2T steps of the autocorrelation function requires only T sparse real matrix-vector multiplications. We describe and compare different schemes, effectively corresponding to different choices of the energy-dependent absorbing potential, and test them numerically by calculating resonances of the HCO molecule. Our numerical tests suggest an optimal scheme that provide accurate estimates for most resonance states. | |
| dc.description | 12 pages, 5 figures | |
| dc.identifier | https://arxiv.org/abs/physics/0204049 | |
| dc.identifier | http://arxiv.org/abs/physics/0204049 | |
| dc.identifier.uri | http://salesiana.dossiersoluciones.com/handle/123456789/84663 | |
| dc.subject | Chemical Physics | |
| dc.title | Further generalization and numerical implementation of pseudo-time Schroedinger equations for quantum scattering calculations | |
| dc.type | text |