No abstract

The valence electronic structures of Fe, Co and Ni have been investigated with Empirical ElectronTheory of Solids and Molecules. The magnetic moments, Curie temperature, cohesive energy and melting point have been calculated according to the valence electronic structure. These calculations fit the experimental data very well. Based on the calculations, the magnetic moments are proportional to the number of 3d magnetic electrons. Curie temperatures are related to the magnetic electrons and the bond lengths between magnetic atoms. Cohesive energies increase with the increase of the number of covalent electrons, and the decrease of the number of magnetic and dumb pair electrons. The melting point is mainly related to the number of covalent electron pairs distributed in the strongest bond. The contribution from the lattice electrons is very small, the dumb pair electrons weaken the melting point; however, the contribution to melting point of the magnetic electrons can be neglected. It reveals that the magnetic and thermal properties are closely related to the valence electronic structures, and the changes or transitions between the electrons obviously affect the physical properties. valence electronic structures, Curie temperature, magnetic moment, cohesive energy, melting pointThe magnetism of the three ferromagnetic transition metals Fe, Co, and Ni is archetypal to the whole subject of metallic magnetism. It would seem necessary to understand the properties of these pure metals before attempting to understand those of the ferromagnetic transition metal alloys. In this paper, the valence electronic structures of Fe, Co, and Ni have been investigated with Empirical Electron Theory of Solids and Molecules (EET), then the magnetic moment, Curie temperature, cohesive energy and melting point have been calculated according to the valence electronic structure, and the calculations are compared with the First-Principle calculations. EET was put forward by Yu [1] in 1978 after he had researched energy band theory and Pauling's [2] covalent bond theory in systems. Meanwhile, the physical and chemical properties of 78 elements of the first six periods in the periodic table of elements, their compounds and alloys are studied to check and systemize EET. The main body of EET [3][4][5] is four hypotheses and the Bond Length Difference Method (BLD).