PENENTUAN STRUKTUR COBALT BERDASARKAN POLA DIFRAKSI ELEKTRON DENGAN MENGGUNAKAN SOFTWARE MATLAB VERSI R2008b

Abstract

The determination of crystal structure of Cobalt is difficult to be evaluated manually. Therefore, it is necessary to perform a computer calculation of the lattice parameters of Cobalt. In order to determine the lattice parameters of Cobalt, two programs have been developed using Matrix Laboratory (MatLab) version R2008b. The first program is called menu program to store the input data that is required in the calculation of the lattice parameters (a & c). The second program is the main program to perform calculations of the lattice parameters according to input data from the program menu. The data used in this research is electron diffraction pattern of Cobalt which was obtained from literature. The radius of each ring of the diffraction pattern was measured using a vernier caliper. These value were input into the program menu. The main program will calculate the value of distance between the plane in the crystal (dhkl). After that, the main program will continue to calculate the lattice parameters for all possible planes in the hexagonal crystal system. Finally, it will select for all possible planes in hexagonal crystal system that same value of the lattice parameters a and c. The results show that the a computer calculation of the lattice parameters a and c for different hkl is a = 2,499 Å and c = 4,054 Å. Results of a computer calculation are compared with the literature value through reliability index. The result is <1 (mean data obtained less than 10%), so the data in this study is acceptable.