Accession Number : ADA258534


Title :   Surface Pi Bonding and the Near-First-Order Desorption Kinetics of Hydrogen from Ge(100)2x1.


Descriptive Note : Technical rept.,


Corporate Author : RICE UNIV HOUSTON TX DEPT OF CHEMISTRY


Personal Author(s) : D'Evelyn, Mark P ; Cohen, Stephen M ; Rouchouze, Eric ; Yang, Yuemei L


Full Text : https://apps.dtic.mil/dtic/tr/fulltext/u2/a258534.pdf


Report Date : 11 Dec 1992


Pagination or Media Count : 12


Abstract : We show by temperature-programmed desorption that hydrogen desorbs from Ge(100)2xl near 570 K with near-first-order kinetics, similar to the behavior of hydrogen on Si(100)2xl. The near-first-order desorption Kinetics are attributed to pairing on surface dimers induced by the n bond on unoccupied dimer atoms, and a pairing enthalpy of 5 + or - 1 kcal/mol is inferred. However, a comparison between the pairing enthalpies for H atoms on Ge(100) and Si(100) with the electronic structure of the respective clean surfaces indicates that estimates of the pi bond strength based on the surface band structure do not correlate with the propensity for pairing.


Descriptors :   *HYDROGEN , *SURFACES , *KINETICS , *CHEMICAL BONDS , *DESORPTION , *GERMANIUM , ELECTRONICS , TEMPERATURE , COMPARISON , DIMERS , ENTHALPY , SILICON , SURFACE CHEMISTRY , CHEMISTRY , ESTIMATES , STRUCTURES , ATOMS , SEMICONDUCTORS


Subject Categories : Inorganic Chemistry
      Physical Chemistry
      Polymer Chemistry


Distribution Statement : APPROVED FOR PUBLIC RELEASE