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Using the density-functional-theory based ab initio method, the authors determine the Ehrlich–Schwoebel barrier as a function of step thickness. The prototype material system is a Cu⟨110⟩ step of B type on a {111} surface. The calculation results show that the diffusion barrier of an adatom is 0.06eV on a flat Cu{111} surface, 0.16eV down a monolayer step, 0.39eV down a two-layer step, and 0.40eV down a multiple-layer step. The results, particularly the transition from 0.16to0.40eV, will have major impacts on the design of surface facets during synthesis of thin films and nanorods.

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and Shun-HuaXIANG Taken the~efining process in an 18t AOD vessel for example. the "back-attack" phenomena of the horizontal rotating and non-rotating gas jets and their effects on the erosion and wear of the refractory lining were investigated in a water model. For this refining process, the two-tuyere (

We present a simple but accurate scheme to compute the thermodynamic properties of crystalline solids in a wide range of pressure and temperature based on ab initio calculations. Compared to the method based on ab initio thermodynamic-integration techniques, our approach can reduce dramatically the number of ab initio molecular-dynamics simulations needed in the calculations of the intrinsic anharmonic effect neglected in the conventional quasiharmonic approximation. Taking tungsten as an example, we show that its thermal properties including the linear thermal-expansion coefficient and the equation of state ͑EOS͒ at high pressures and temperatures can be calculated accurately. The precise EOS of W for the pressure up to 500 GPa and the temperature up to 10 000 K may serve as a pressure scale. This method may be able to be extended to the study of solid-solid phase transitions of various crystalline solids, including some alloys.