Menu

ناقشة وعلى قاعد المرحوم جابر اعليو طالب الماجستير محمد نزار محمد قسم علوم الفيزياء وقد كانت النتيجة (امتياز)

مناقشة طالب من كلية العوم محمد نزار محمدSince a recent experimental data on Compton profile were available on some 3d transition metals and their alloys it was thought to held theoretical calculations on some of them and Compare them with the mentioned experimental ones, as follows :
The present study is devoted to calculate the Compton profile and investigate the electronic structure for two elements of 3d-transitions metals namely [Fe and Ni] and [Fe-Ni] alloys using the RFA and FE models to calculate their electronic structures and compare them with other experimental as well as theoretical studies.
These theoretical Compton profile data have been used to compute the cohesive energy of Iron and Nickel for the first time and compared with available measured data.

abstract

مناقشة طالب الماجستير محمد نزار محمدThe quantum theory of scattering of electromagnetic waves by charged particles is known as Compton effect which can give us valuable information about the electronic structure of transition metals, alloys and compounds .Due to that Compton profile is sensitive to the state of the valence electrons of atoms which combine to form the condensed phase of material , in other words, the experiment of Compton scattering provides an information about electron momentum in the sample which is described by the projection of the electron momentum density ρ( (p ) ⃗) on the direction of scattering vector, were ρ( (p ) ⃗) represents the square of the momentum wave function .This thesis contains three parts:
Part I:
Compton profiles of (bcc-Fe)have been calculated by using the renormalized –free atom model choosing several مناقشة طالب الماجستير محمد نزار محمدconfigurations (3d6-x 4s1+x) whereas (x = 0 to 1 step 0.1) and free electron model. The theoretical results have been compared with the available experimental values. It can be seen that the (RFA) model values give better agreement with the experimental ones for the (3d6.3 4s1.7) configuration before convolution and (3d6.7 4s1.3) configuration after convolution .also computed the cohesive energy of Iron and compared it with the available data.
Part II:
Compton profile of (Ni) has been calculated by employing the renormalized-free atom model and free electron model, several configurations were chosen for (3d-4s) subshells. Results have been compared with recent data . It is seen that the RFA calculation for (3d8.4-4s1.6) configuration before convolution and (3d8.8-4s1.2) configuration after مناقشة طالب الماجستير محمد نزار محمد convolution gives a better agreement with the experiment. This theoretical Compton profile data have been used to compute the cohesive energy of Nickel for the first time and compared it with the available data.
Part III:
A study of the electronic state in Fe0.64-Ni0.36 (Invar) and Fe0.5-Ni0.5 alloys using the Compton scattering technique was reported. The superposition model was applied to calculate the total Compton profiles for the two alloys by employing the calculated values from part I&II of the constituent .The data on both alloys are in very good agreement with the superposition of Compton profiles of the pure constituent metals, weighted by their compositions.

Go to top