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The computations of the static and vibrational properties of five alkali metals viz. Li, Na, K, Rb and Cs to second order in local model potential is discussed in terms of real-space sum of Born von Karman central force constants. The exchange and correlation functions due to Hartree (H) and Ichimaru-Utsumi (IU) are used to investigate influence of screening effects. Results for the lattice constants i.e.C₁₁, C₁₂, C₄₄, C₁₂-C₄₄, (n) and bulk modulus (n) obtained using the Hartree (H) local field correction function has higher values in comparison with the results obtained for the same properties using Ichimaru-Utsumi (IU) local field correction function. The results for the Shear modulus(C'), deviation from Cauchy’s relation, Poisson’s ratio s, Young modulus Y, propagation velocity of elastic waves, phonon dispersion curves (PDC) and degree of anisotropy A are highly appreciable for the alkali metals. The phonon frequencies of alkali metals in the longitudinal branch are more sensitive to the exchange and correlation effects in comparison with the transverse branches. The phonon dispersion curves (PDC) of pure alkalis are found in qualitative agreement with the available experimental data. While, the frequencies in the longitudinal branch are suppressed due to IU-screening function than the frequencies due to static H-screening function.