Analysis of Valence Electron Theory on the Catalytic Mechanism of Diamond Single Crystal Growth


Article Preview

Large numbers of experimental results show that carbides Me3C (Me means Fe, Ni, Co, Mn) are the primary carbon source to form diamond structure under the high temperature and high pressure (HPHT). In this paper, based on the empirical electron theory of solids and molecules (EET), the valence electron structure (VES) and interface structure factors of diamond and various carbides are calculated, and the boundary condition of electron movement in the improved Thomas- Fermi-Dirac theory by Cheng (TFDC) is applied to the carbide/diamond interfaces. It is found that the electron density of crystal plane in Me3C formed by C-C bonds is continuous with that in diamond at the first order of approximation. Compared with Ni-based carbides [Ni3C, (NiMn)3C)], the electron density difference of Fe-based carbides [Fe3C, (FeNi)3C, (FeMn)3C]/diamond interfaces is lower, and that of (FeNi)3C/diamond interface is minimum. The results show that the energy needed to transform carbon atomic groups into diamond structure is lower for Fe-based carbides than Ni-based carbides.



Key Engineering Materials (Volumes 353-358)

Edited by:

Yu Zhou, Shan-Tung Tu and Xishan Xie




L. Li et al., "Analysis of Valence Electron Theory on the Catalytic Mechanism of Diamond Single Crystal Growth", Key Engineering Materials, Vols. 353-358, pp. 2998-3001, 2007

Online since:

September 2007




[1] B. L. Solozhenko and B. Z. Turkevich: Journal of Physical Chemistry. Vol. 106 (2002), p.6634.

[2] E. Plvel, Gh. Baluta and D. Barb: Journal of Materials Science. Vol. 28 (1993), p.1645.

[3] L. W. Yin, M. S. Li and J. J. Cui: Journal of Crystal Growth. Vol. 234 (2002) , p.1.

[4] Z. L. Liu , Z. L. Li and W. D. Liu. Valence Electron Structure of Interfaces and their Properties. Beijing: Science Press (2002).

[5] Z. L. Liu, Z. L. Li and Z. G. Sun: Metallurgical and Materials Transactions. A (1999), p.2757.

[6] B. Xu, Li M S and Cui J J: Material Science & Engineering. Vol. 396(2005), p.352.

[7] B. Xu, J. J. Cui and M. S. Li: China Physical Letter. Vol. 2 (2005), p.478.

[8] Z. Y. Hao and Y. F. Chen: Synthetic Diamond. Changchun: Jilin University Press (1996), p.95.