CALCULATION OF ELASTIC-SCATTERING CROSS-SECTIONS OF LOW-ENERGY ELECTRONS BY PBH4 AND SNH4

We report elastic integral, differential, and momentum transfer cross sections from 10 to 30 eV for electron scattering by SnH4 and PbH4, ob tained using the Schwinger Multichannel Method with Pseudopotentials [ M. H. F. Bettega, L. G. Ferreira, and M. A. P. Lima, Phys. Rev. A 47, 1111 (1993)]. With these molecules we close the series of XH(4) molecu les, with X=C, Si, Ge, Sn, Pb. We compare the present results with tho se obtained previously for CH4, SiH4, and GeH4. We find similarities i n the cross sections for SiH4, GeH4, SnH4, and PbH4 and a distinctive behavior of CH4. We discuss the role of the center atom size in the sc attering process. To our knowledge this is the first ab initio calcula tion of the SnH4 and PbH4 electron scattering cross sections. (C) 1995 American Institute of Physics.