Energetics of single- and double-layer steps on the Si(001)2X1 surface calculated using the extended Brenner empirical potential

The extended Brenner potential has been shown to provide a good description of the (001) and (111) surfaces of silicon. In this paper, this empirical potential is employed to study the energetics of steps on the Si(001)2x1 su rface. Particular attention has been paid to the dependence of the step ene rgies on the width of the terraces and the number of substrate layers. Form ation energies for both the single-layer S-A and S-B steps, and the double layer D-A and D-B steps, have been determined. All of the formation energie s are found to be negative. Values of the step-step and surface stress inte raction energy coefficients are also determined. The correlation of these r esults with experiment and previous theoretical calculations is discussed.