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We report analytical results for pair distribution function g(r) and structure factor S(q) for warm dense partially ionized aluminum plasma at metallic density employing a numerical scheme going beyond one component plasma (OCP) model. It is built on the effective charged hard sphere (e-CHS) based two-parameter model; packing fraction (η) and ion plasma parameter (Γ), but simplified to convert into a one-parameter scheme. Ion interaction through electron screening effect is determined within the linear response theory for dielectric function and a description beyond the random phase approximation (RPA) is incorporated through the local field correction. We employ a local pseudopotential comprises of a Hartree potential, exchange-correlation potential based on the local density approximation and a repulsive delta-function to achieve the orthogonalization effect of free electron states to the core states. Results for g(r) and S(q) are fitted to experimental and recent ab initio simulations findings to deduce effective charge in warm Al- plasma. We examine our scheme for temperature ranging from melting 0.08 eV up to 15 eV. Fitted parameters are compared and analyzed with quantum two component plasma (Q-TCP) model parameters. Good agreement with Q-TCP compared to OCP is discussed, which exemplifies the importance of proper account for exchange and correlation effect. The proposed scheme is further tested for some important thermodynamic quantities and results so deduced are validated with reported findings. Overall agreement for computed physical quantities confirms the need of screened electron-ion interaction and a scheme going beyond the OCP model for accurate determination for structure and thermodynamics of dense plasma. [ABSTRACT FROM AUTHOR]

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]