\subsubsection{The Tersoff potential}
-Ther Tersoff potential \cite{tersoff1} \ldots
+Tersoff proposed an empirical interatomic potential for covalent systems.
+The Tersoff potential explicitly incorporates the dependence of bond order on local envirenments, permitting an improved description of covalent materials.
+Tersoff applied the potential to silicon \cite{tersoff_silicon1,tersoff_silicon2,tersoff_silicon3}, carbon \cite{tersoff_carbon} and also to multicomponent systems like $SiC$ \cite{tersoff_multi}.
+
+The basic idea is that, in real systems, the bond order depends upon the local environment.
+An atom with many neighbours forms weaker bonds than an atom with few neighbours.
+
+
\begin{equation}
V_{ij} = f_C(r_{ij}) [ f_R(r_{ij}) + b_{ij} f_A(r_{ij}) ]
\bibitem{stillinger_weber}
F. H. Stillinger, T. A. Weber.
Phys. Rev. B 31 (1985) 5262.
- \bibitem{tersoff1}
+ \bibitem{tersoff_silicon1}
+ J. Tersoff.
+ Phys. Rev. Lett. 56 (1986) 632.
+ \bibitem{tersoff_silicon2}
+ J. Tersoff.
+ Phys. Rev. B 37 (1988) 6991.
+ \bibitem{tersoff_silicon3}
+ J. Tersoff.
+ Phys. Rev. B 38 (1988) 9902.
+ \bibitem{tersoff_carbon}
+ J. Tersoff.
+ Phys. Rev. Lett. 61 (1988) 2879.
+ \bibitem{tersoff_multi}
J. Tersoff.
Phys. Rev. B 39 (1989) 5566.
\bibitem{example}