Tight-Binding molecular dynamics simulation: Structural properties of liquid molybdenum at melting.

We report classical molecular dynamics (MD) simulation results for structural information of liquid Molybdenum at melting temperature. Effective interatomic interaction is deduced within the tight-binding second- moment approximation and extended up to three neighbor distance, as proposed by Karolewski [Radiation Effect & Defects in Solids, 153 (2001) 239]. By simultaneously varying density (ρ) and temperature (T), and observing the simulated system at a regular interval of time, we have estimated melting temperature (2903 K) and corresponding density (8.4915 g/cm3) is in agreement with the experimental and recent ab initio MD findings. Further, the pair-correlation function g(r) deduced at presently estimated melting temperature and density is analyzed in terms of coordination number and in reference to the assumed effective interaction potential. Unexpected large coordination number (12.84) found for such a BCC → liquid transition may be attributed to the limitation of the potential. Further, the Fourier transform of g(r) is used to derive static structure factor S(k) and its long wavelength limit is exploited to find compressibility. Relative position and nature of the first and the second peak in S(k) reveal following points: (i) first peak is symmetrical and (ii) the ratio of the position of the second peak to that of the first peak is 1.9013. This confirms that the system is fully melted into the normal liquid phase. [ABSTRACT FROM AUTHOR]