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Abstract Using the energy minimization calculations based on an interfacial potential and a first-principles total energy method, respectively, we show that (2 × 2)/(3 × 3) Pb/Cu(111) system is a stable structure among all the [(n − 1) × (n − 1)]/(n × n) Pb/Cu(111) (n = 2, 3,…, 12) structures. The electronic structure calculations indicate that self-organized ordered Pb semi-clusters arrays are formed on the first Pb monolayer of (2 × 2)/(3 × 3) Pb/Cu(111), which is due to a strain-release effect induced by the inherent misfits. The Pb semi-clusters structure can generate selective adsorption of atoms of semiconductor materials (e.g., Ge) around the semi-clusters, therefore, can be used as a template for the growth of nanoscale structures with a very short periodic length (7.67 Å).

The bonding energies of surface atoms of intermetallic compounds were computed to predict qualitatively a selective field evaporation of one atomic species under typical conditions for field-ion microscopy. It was assumed that atoms with smaller bonding energies will be eliminated selectively during field evaporation. Comparison of calculations with those of other models indicated that neither conventional selective field evaporation nor the charge transfer can elucidate on all the observations.

We present an exact mathematical description of beam shaping and indicate that a rigorous solution does not exist: only an optimal solution can be found. An optimization method is proposed to search for the solution. The simulation results for an example are given in detail.

Bruns's version of the 1-D arithmetic Fourier transform was developed to a 2-D case. The algorithm was accomplished by a computer program to carry out an example of the Fourier transform of 2-D Gaussian function. Results reveal that the error of the algorithm with zero-order interpolation is tolerable for some applications. The new algorithm was found less complex over previous algorithms and is applicable to even and noneven 2-D functions.

Chen's lattice inversion method was applied to first-principles cohesive energy curves to determine the effective interatomic potentials between distinct atoms in such intermetallics as AlLi3, Al3Li, FeAl, Fe3Al, NiAl, Ni3Al, Al3Cr and FeCr. The phonon dispersions and linear thermal expansion of certain intermetallic compounds were identified using the resulting potentials. The site preference of Cr in D03-ordered Fe3Al was also derived.

The ab initio total energies of alkali chloride crystals in B1 (rock salt), B2 (CsCl-type), B3 (zinc blende) and P4/mmm structures are calculated by ultrasoft pseudopotential method in this paper. Based on the different combinations of these total energies, the effective charges on ions are determined for long-range Coulomb interaction, and the short-range potential curves are obtained by the lattice inversion method. As the test for the quality of potentials, the static properties of ACl in the rock salt phase are calculated. The results are in good agreement with the experimental data. And the calculated lattice energies for ACl in wurtzite, CuAu, NiAs, and litharge structures are consistent with the predictions of pseudopotential calculations. In terms of the molecular dynamics simulations, the temperature dependences of volume, bulk modulus, and elastic constants are also investigated from room temperature to 800 K, the results are in good agreement with the experimental values. This indicates that the new interionic potentials are valid over a wide range of interionic separations and coordination numbers. © 2003 American Institute of Physics. [ABSTRACT FROM AUTHOR]