Hostname: page-component-78c5997874-ndw9j Total loading time: 0 Render date: 2024-11-10T08:27:52.446Z Has data issue: false hasContentIssue false
  • English
  • Français

Generating Structural Models of Amorphous Tetrahedral Carbon: Basis set Dependencies

Published online by Cambridge University Press:  10 February 2011

Peter A. Schultz  and
E. B. Stechel
Peter A. Schultz
Affiliation:
Sandia National Laboratories, Albuquerque, NM 87185–1111
E. B. Stechel
Affiliation:
Sandia National Laboratories, Albuquerque, NM 87185–1111
Get access

Abstract

We present the results of a systematic first-principles investigation of the requirements for developing realistic and reliable structural models for amorphous tetrahedral carbon (a-tC) and relate those structural models to the physical properties of this material. Within a linear combination of atomic orbitals formulation of density functional theory, we show that a large variational flexibility is required to accurately treat the highly defected and strained structures that can exist in a-tC. The average strain in the a-tC lattice is predicted to be roughly twice the strain of having all carbon atoms in three-member rings. A key figure of merit of a structural model, the proportion of three-fold bonded atoms, is shown to triple in going from a minimal basis description of a structure to a high quality basis. The basis-converged calculations agree well with experimental observables, such as the presence of four-member rings, lack of dangling bonds, and a significant gap. The simulations predict a much larger proportion of three-fold atoms than estimated in simple analyses of EELS and neutron scattering experiments. We show that the larger three-fold fraction is indeed consistent with the properties of a-tC, and imply that there are flaws in the simplifying assumptions that go into constructing experimental estimates of coordination numbers. These results highlight the perils of applying highly simplified theoretical models for a-tC before the correct physics has been identified and built into the models.

Type
Research Article
Information
MRS Online Proceedings Library (OPL) , Volume 498: Symposium AA – Covalently Bonded Disordered Thin-Film Materials , 1997 , 11
Copyright
Copyright © Materials Research Society 1998

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

REFERENCES

1. Cuomo, J.J., Doyle, J.P., Bruley, J., and Liu, J.C., J. Vac. Sci. Technol. A 9, 2210 (1991).Google Scholar
2. Cockayne, D.J.H. and McKenzie, D.R., Acta. Cryst. A44, 870 (1988).Google Scholar
3. Berger, S.D., McKenzie, D.R., and Martin, P.J., Phil. Mag. Lett. 57, 285 (1988).Google Scholar
4. McKenzie, D.R., Muller, D., and Pailthorpe, B.A., Phys. Rev. Lett. 67, 773 (1991).Google Scholar
5. Gaskell, P.H., Saeed, A., Chieux, P., and McKenzie, D.R., Phys. Rev. Lett. 67, 1286 (1991); Phil. Mag. B 66, 155 (1992).Google Scholar
6. Gilkes, K.W.R., Gaskell, P.H., and Robertson, J., Phys. Rev. B 51, 12303 (1995).Google Scholar
7. Zelez, J., J. Vac. Sci. Technol. A 1, 305 (1983).Google Scholar
8. Veerasamy, V.S., Amaratunga, G.A.J., Milne, W.I., Hewitt, P., Falion, P.J., McKenzie, D.R., and Davis, C.A., Diamond Relat. Mater. 2, 782 (1993);Google Scholar
Veerasamy, V.S., Amaratunga, G.A.J., Davis, C.A., Timbs, A.E., Milne, W.I., and McKenzie, D.R., J. Phys. Condens. Matter 5, 169 (1993).Google Scholar
9. Galli, G., Martin, R.M., Car, R., and Parrinello, M., Phys. Rev. Lett. 42, 555 (1989); Phys. Rev. B 42, 7470 (1990).Google Scholar
10. Marks, N.A., McKenzie, D.R., Pailthorpe, B.A., Bernasconi, M., and Parrinello, M., Phys. Rev. Lett. 76, 768 (1996).Google Scholar
11. Drabold, D.A., Fedders, P.A., and Grumbach, M.P., Phys. Rev. B 54, 5480 (1996).Google Scholar
12. Marks, N.A., McKenzie, D.R., Pailthorpe, B.A., Bernasconi, M., and Parrinello, M., Phys. Rev. B 54, 9703 (1996).Google Scholar
13. Drabold, D.A., Fedders, P.A., and Stumm, P., Phys. Rev. B 49, 16415 (1994).Google Scholar
14. Wang, C.Z. and Ho, K.M., Phys. Rev. Lett. 71, 1184 (1993).Google Scholar
15. Wang, C.Z. and Ho, K.M., J. Phys.: Condens. Matter 6, L239 (1994).Google Scholar
16. Wang, C.Z. and Ho, K.M., Phys. Rev. B 50, 12429 (1994).Google Scholar
17. Frauenheim, Th., Blaudeck, P., Stephan, U., and Jungnickel, G., Phys. Rev. B 48, 4823 (1993).Google Scholar
18. Stephan, U., Frauenheim, Th., Blaudeck, P., and Jungnickel, G., Phys. Rev. B 49, 1489 (1994).Google Scholar
19. Frauenheim, Th., Jungnickel, G., Köhler, Th., and Stephan, U., J. Non-Cryst. Solids 182, 186 (1995).Google Scholar
20. Sankey, O.F. and Niklewski, D.J., Phys. Rev. B 40, 3979 (1989).Google Scholar
21. Harris, J., Phys. Rev. B 31, 1770 (1985).Google Scholar
22. Hohenberg, P. and Kohn, W., Phys. Rev. 136, B864 (1964).Google Scholar
23. Kohn, W. and Sham, L.J., Phys. Rev. 140, A1133 (1965); see alsoGoogle Scholar
Theory of the Inhomogeneous Electron Gas, edited by Lundqvist, S. and March, N.M. (Plenum, New York, 1983).Google Scholar
24. Drabold, D.A., Stumm, P., and Fedders, P.A., Phys. Rev. Lett. 72, 2666 (1994).Google Scholar
25. Nelson, J.S., Stechel, E.B., Wright, A.F., Plimpton, S.J., Schultz, P.A., and Sears, M.P., Phys. Rev. B 52, 9354 (1995).Google Scholar
26. Sears, M.P. and Schultz, P.A., QUEST Program, unpublished.Google Scholar
27. Hamann, D.R., Phys. Rev. B 40, 2980 (1989).Google Scholar
28. Perdew, J. and Zunger, A., Phys. Rev. B 23, 5048 (1981).Google Scholar
29. Ceperley, D.M. and Alder, B.J., Phys. Rev. Lett. 45, 566 (1980).Google Scholar
30. Pulay, P., Mol. Phys. 17, 197 (1969).Google Scholar
31. Johnson, D.D., Phys. Rev. B 38, 12807 (1988).Google Scholar
32. Car, R. and Parrinello, M., Phys. Rev. Lett. 55, 2471 (1985).Google Scholar
33. Schultz, P.A. and Stechel, E.B., Phys. Rev. B, in press.Google Scholar
34. Porezag, D., Frauenheim, Th., Köhler, Th., Seifert, G., and Kascher, R., Phys. Rev. B 51, 12947 (1995).Google Scholar
35. Falion, P.J., Veerasamy, V.S., Davis, C.A., Robertson, J., Amaratunga, G.A.J., Milne, W.I., and Koskinen, J., Phys. Rev. B 48, 4777 (1993).Google Scholar
36. McCulloch, D.G., Gerstner, E.G., McKenzie, D.R., Prawer, S., and Kalish, R., Phys. Rev. B 52, 850 (1995).Google Scholar