In brief, the calculations were performed by solving the radial Schrodinger equation for each partial wave component on the ground state singlet adiabatic electronic eigenenergy curves. This state is the ground state energy curve of LiH+ which correlate asymptotically (separated atoms limit) to Li+ and H(1s). The potential we used as our starting point in the present calculations were calculated by computational chemistru code NWChem, using CCSDT procedure in the range of internuclear separations 0.1-30 a.u.
In order to obtain convergence in partial waves (impact parameter) for low energy elastic scattering, we extended these potential energy curves to larger distances by fitting them to the dipole polarization potential (dipole polarizability from Reference 5).
Much as in our previous calculations, the radial integration was carried out using Johnson's logarithmic derivative method, beginning the integration at an internuclear separation of 0.1 a.u. and with a step of 0.0001 a.u., and then matching the solution to plane waves at 200 a.u. Convergence in partial waves is monitored until the partial amplitude, al, satisfies 1-Re(al) < 10-6 and Im(al) < 10-6 for 20 consecutive values of l. The elastic differential cross section is computed at 768 angles between 0 and pi, to facilitate Gauss-Legendre integration and to assure that all the oscillations of the differential cross section are represented accurately enough to assure convergence during this integration. The procedure is repeated for 61 energies spanning the center of mass collision energy range of 0.0001-100 eV.
Important notes and updates
- 1. The data have been posted as of 10/30/09. Any updates will be documented here.
Publications
The two basic references for these cross sections are:
P.S. Krstic and D. R. Schultz, 2009 J. Phys. B: At. Mol. Opt. Phys. 42, 065207 doi: 10.1088/0953-4075/42/6/065207 "Elastic and related transport cross sections for singly charged ionatom scattering of light metals (Li, Be, B) and hydrogen"
P.S. Krstic and D. R. Schultz, Phys. Plasmas 16, 053503 (2009); doi:10.1063/1.3126549 "Mean free paths and elastic and related transport cross sections for neutrals and singly charged ions of Li, Be, and B in hydrogen plasmas"
The results for collisions among all isotopic combinations of hydrogen ions, atoms, and molecules are described in the following references and here. The data form the basis for a volume of recommended elastic and transport related cross sections (reference 1), and many details of the calculations, their physical interpretation, and their inter-relationships are detailed in references 2-4.
- 1. ``Elastic and related transport cross sections for collisions
among isotopomers of H+ + H, H+ + H2,
H+ + He, H + H, and H + H2'', P.S. Krstic and
D.R. Schultz, Atomic and Plasma-Material Data for Fusion
8 ,1 (1998). (Postscript file containing the introduction, basic theoretical description, comparison with existing results, scaling relations, description of tables and graphs, and references - approximately 70 pages, 1.68 Mb, approximately 650 pages of graphs and tables omitted). - 2. ``Elastic scattering and charge transfer in slow collisions:
Isotopes of H and H+ colliding with isotopes of H and
with He,'' P.S. Krstic and D.R. Schultz, J. Phys. B
32 , 3485 (1999). (Postscript (5.48 Mb)). - 3. ``Consistent definitions for, and relationships among, cross
sections for elastic scattering of hydrogen ions, atoms, and molecules,''
P.S. Krstic and D.R. Schultz, Phys. Rev. A
60 , 2118 (1999). (Postscript (4.21 Mb)). - 4. ``Elastic and vibrationally inelastic slow collisions: H + H2, H+ + H2,'' P.S. Krstic and D.R. Schultz, J. Phys. B 32, 2415 (1999). (Postscript (3.53 Mb)).
- 5. "Physics of Highly Charged Ions", R.K. Janev, L.P. Presnyakov, and V.P. Shevelko, Springer-Verlag, New York (1985).
