الملخص

ABSTRACT In the present work a numerical optimization model is constructed which is based on the experimental pressure (pexp) and experimental recoilless fraction ratio (rfexp=fp/f0) data in order to explain the pressure effect on Gruneisen parameters(, q) and Debye temperature.The model was able to compute the optimum q value for copper, the observed optimum value for q was used with Debye approximation at room temperature under pressure to calculate the recoilless fraction ratio rftheor=fp/fo for (Fe57-Cu), It has been found that the calculated results of (f-fraction) are in good agreement with the experimental data of recoilless fraction ratio.