Journal of Chemical Physics
The Journal of Chemical Physics
Search:
   
 
 
 
Previous Article
Coriolis interaction in polyatomic molecules: A classical coupled spin representation
A coupled spin representation is introduced to describe the classical dynamics of two vibrational modes of a polyatomic molecule coupled by Coriolis interaction to overall molecular rotation. The mech...
Next Article
Molecular-dynamics simulation for a model nonadiabatic proton transfer reaction in solution
It is shown how a dynamical theory for proton transfer rates in solution can be implemented in a molecular-dynamics simulation for a model reaction system. The reaction is in the nonadiabatic limit, i...

Interaction of silicon cluster ions with ammonia: Annealing, equilibria, high temperature kinetics, and saturation studies

J. Chem. Phys. 94, 3607 (1991); doi:10.1063/1.459732

Issue Date: 1 March 1991

You are not logged in to this journal. Log in

Martin F. Jarrold, Yumi Ijiri, and Urmi Ray
AT&T Bell Laboratories, Murray Hill, New Jersey 07974
The results of extensive studies of the chemical reactions of size selected silicon cluster ions (containing up to 70 atoms) with ammonia are described. At room temperature all clusters react at close to the collision rate and collisional annealing of the clusters does not influence their reactivity. At temperatures slightly above room temperature (~400 K) it is possible to establish an equilibrium. Binding energies of ammonia to the silicon clusters of ~1 eV were determined from measurements of the equilibrium constants as a function of temperature. These small binding energies indicate that molecular adsorption occurs at close to room temperature. Saturation experiments reveal that ammonia only binds molecularly to a small number of sites on the clusters. In contrast, on bulk silicon surfaces at room temperature, rapid dissociative chemisorption occurs until all the surface dangling bonds are saturated. At temperatures above ~470 K another process, probably dissociative chemisorption, becomes important. Absolute rate constants were measured for clusters with 30–70 atoms at a temperature of 700 K where the dissociative chemisorption process dominates. The sticking probabilities at this temperature are between 10−3 and 10−5, two to four orders of magnitude smaller than on bulk silicon at 700 K. The Journal of Chemical Physics is copyrighted by The American Institute of Physics.
History: Received 10 September 1990; accepted 30 November 1990
Permalink: http://link.aip.org/link/?JCPSA6/94/3607/1
BUY THIS ARTICLE   (US$24)
Download PDF (1659 kB) View Cart

KEYWORDS and PACS

Keywords
PACS
  • 36.40.+d
    Studies of special atoms and molecules Atomic and molecular clusters
  • 82.30.Fi
    Physical chemistry Specific chemical reactions; reaction mechanisms Ionmolecule, ionion, and charge-transfer reactions
  • 82.65.My
    Physical chemistry Surface and interface chemistry Chemisorption
  • 82.20.Pm
    Physical chemistry Chemical kinetics Measurements of rate constants, reaction cross sections, and activation energies
  • YEAR: 1990-91

PUBLICATION DATA

ISSN:
0021-9606 (print)   1089-7690 (online)
Publisher:
AIP is a member of CrossRef AIP

REFERENCES (29)

For access to fully linked references, you need to log in. For access to fully linked references, you need to Log in.
  1. U. Ray and M. F. Jarrold, J. Chem. Phys. 93, 5709 (1990).
  2. J. L. Elkind, J. M. Alford, F. D. Weiss, R. T. Laaksonen, and R. E. Smalley, J. Chem. Phys. 87, 2397 (1987).
  3. J. M. Alford and R. E. Smalley, Mat. Res. Soc. Symp. Proc. 131, 3 (1989).
  4. L. R. Anderson, S. Maruyama, and R. E. Smalley, Ethylene Chemisorption on Levitated Silicon Cluster Ions: Evidence for the Importance of Annealing, Chem. Phys. Lett. (submitted, 1990).
  5. S. Maruyama, L. R. Anderson, and R. E. Smalley, J. Chem. Phys. 93, 5349 (1990).
  6. J. M. Alford, R. T. Laaksonen, and R. E. Smalley, Ammonia Chemisorption Studies on Silicon Cluster Ions, J. Chem. Phys. (submitted, 1990).
  7. M. F. Jarrold, J. E. Bower, and K. M. Creegan, J. Chem. Phys. 90, 3615 (1989).
  8. K. M. Creegan and M. F. Jarrold, J. Am. Chem. Soc. 112, 3768 (1990).
  9. M. F. Jarrold, U. Ray, and K. M. Creegan, J. Chem. Phys. 93, 224 (1990).
  10. Q.-L. Zhang, Y. Liu, R. F. Curl, F. K. Tittel, and R. E. Smalley, J. Chem. Phys. 88, 1670 (1988).
  11. M. F. Jarrold and J. E. Bower, J. Phys. Chem. 92, 5702 (1988).
  12. Y. Ijiri and M. F. Jarrold (unpublished).
  13. T. Su and M. T. Bowers, J. Chem. Phys. 58, 3027 (1973);
  14. Int. J. Mass Spectrom. Ion Phys. 12, 347 (1973);
    17, 211 (1975);
    Gas Phase Ion Chemistry, edited by M. T. Bowers (Academic, New York, 1979), Vol. 1.
  15. E. K. Parks, K. Liu, S. C. Richtsmeier, L. G. Pobo, and S. J. Riley, J. Chem. Phys. 82, 5470;
  16. T. D. Klots, B. J. Winter, E. K. Parks, and S. J. Riley, ibid. 92, 2110 (1990).
  17. D. J. Trevor, D. M. Cox, K. C. Reichmann, R. O. Brickman, and A. Kaldor, J. Phys. Chem. 91, 2598 (1987).
  18. Handbook of Chemistry and Physics, 69th ed., edited by R. C. Weast (CRC Press, Boca Raton, 1988).
  19. K. Raghavachari, J. Chandrasekhar, M. S. Gordon, and K. J. Dykema, J. Am. Chem. Soc. 106, 5853 (1984).
  20. K. Raghavachari and C. M. Rohlfing, J. Chem. Phys. 89, 2219 (1988).
  21. B. G. Koehler, P. A. Coon, and S. M. George, J. Vac. Sci. Technol. B 7, 1303 (1989).
  22. R. Wolkow and Ph. Avouris, Phys. Rev. Lett. 60, 1049 (1988);
  23. Ph. Avouris, F. Bozso, and R. J. Hamers, J. Vac. Sci. Technol. B 5, 1387 (1987);
    R. J. Hamers, Ph. Avouris, and F. Bozso, Phys. Rev. Lett. 59, 2071 (1987).
  24. F. Bozso and Ph. Avouris, Phys. Rev. B 38, 3937 (1988);
  25. F. Bozso and Ph. Avouris, Phys. Rev. Lett. 57, 1185 (1986).
  26. S. C. Richtsmeier, E. K. Parks, K. Liu, L. G. Pobo, and S. J. Riley, J. Chem. Phys. 82, 3659 (1985).
  27. B. G. Koehler, C. H. Mak, and S. M. George, Surf. Sci. 221, 565 (1989).
  28. P. Gupta, C. H. Mak, P. A. Coon, and S. M. George, Phys. Rev. B 40, 7739 (1989).
  29. U. Ray and M. F. Jarrold, Reactions of Silicon Cluster Ions, Si<sub>n</sub><sup>+</sup> (n = 10−65), with Water, J. Chem. Phys. (in press, 1991).
  30. See, for example, G. Pacchioni and J. Koutecky, J. Chem. Phys. 84, 3301 (1986);
  31. R. Biswas and D. R. Hamann, Phys. Rev. B 34, 895 (1986);
    D. Tomanek and M. Schluter, Phys. Rev. B 36, 1208 (1987);
    D. A. Jelski, Z. C. Wu., and T. F. George, Chem. Phys. Lett. 150, 447 (1988);
    P. Ballone, W. Andreoni, R. Carr, and M. Parrinello, Phys. Rev. Lett. 60, 271 (1988);
    B. P. Feuston, R. K. Kalia, and P. Vashishta, Phys. Rev. B 37, 6297 (1988);
    H.-X. Wang and R. P. Messmer, Phys. Rev. B 41, 5306 (1990).
  32. J. R. Chelikowsky and J. C. Phillips, Phys. Rev. Lett. 63, 1653 (1989).
  33. E. Kaxiras, Phys. Rev. Lett. 64, 551 (1990).
  34. K. Raghavachari, Phase Trans. 24–26, 61 (1990).

CITING ARTICLES

For access to citing articles, you need to log in.
For access to citing articles, you need to Log in.