A real symmetric Lanczos subspace implementation of quantum scattering using boundary inhomogeneities

• Published in: Chemical physics letters Vol. 366; no. 3; pp. 390 - 397
• Main Authors: Reignier, D, Smith, S.C
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 10.12.2002; Elsevier Science
• Subjects: Atomic and molecular collision processes and interactions; Atomic and molecular physics; Chemical reactions, energy disposal, and angular distribution, as studied by atomic and molecular beams; Exact sciences and technology; Physics; Scattering of atoms, molecules and ions; Reactive collision; Inorganic compounds; Reaction probability; Collinear collision; Hydrogen Atoms; Theoretical study; Diatomic molecules; Hydrogen molecules; Lanczos method; Atom-molecule collisions
• ISSN: 0009-2614; 1873-4448
• DOI: 10.1016/S0009-2614(02)01630-5

We present an efficient and robust method for calculating state-to-state reaction probabilities utilising the Lanczos algorithm for a real symmetric Hamiltonian. The method recasts the time-independent Artificial Boundary Inhomogeneity technique recently introduced by Jang and Light (J. Chem. Phys. 102 (1995) 3262) into a tridiagonal (Lanczos) representation. The calculation proceeds at the cost of a single Lanczos propagation for each boundary inhomogeneity function and yields all state-to-state probabilities (elastic, inelastic and reactive) over an arbitrary energy range. The method is applied to the collinear H+H 2 reaction and the results demonstrate it is accurate and efficient in comparison with previous calculations.