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Total energy

Combining equations 2.4, 2.9, 2.11 and 2.14 yields the total energy:


$\displaystyle \mathcal{E}$ $\displaystyle =$ $\displaystyle {1 \over 2}\sum_i\sum_{j\in{\mathcal{N}_i}}\mathcal{E}_{\mathrm{e...
...hrm{Ze}}^{i} + {1 \over 2}\sum_i^N\sum_{j\neq i}\mathcal{E}_{\mathrm{di}}^{i,j}$ (2.15)

$ \mathcal{E}$The total energy in a system

The number of atoms in comparatively small systems is large. Assuming a cubic structure and a lattice spacing of 2.5Å as in iron, cobalt or nickel, a cube of edge length 100nm would contain 6.4$ \times$10$ ^7$ atoms.



Richard Boardman 2006-11-28