Effect of Doping Concentration on Structural Stability and Formation Energy of the Fluorine Doped Hexagonal Molybdenum Dioxide (MoO2). A First Principle Study.

The structural properties of undoped and Fluorine doped Hexagonal Molybdenum dioxide (MoO2) with different doping concentrations have been calculated using Density Functional Theory (DFT) within Generalized Gradient Approximation (GGA) as implemented in Quantum Espresso (QE). The calculated results were for the formation energy of 4.17%, 8.33%, 12.5%, of F doped MoO2 are 232.5eV, 463.0eV, and 698.5eV respectively, which show the variation of energy based on the increase in the doping concentration that led to having the breakage of bond in the structure of the compound. The undoped and 4.17% of F doped MoO2 have three free atoms, which maintain the stability of the structure, but when the doping concentration was increased, the bond breaks simultaneously which led to having four and five free atoms for 8.33%, and 12.5% of F doped MoO2 respectively. This makes 4.17% of F doped MoO2 with 17.09Ry more stable. Similarly, the bond length of undoped MoO2 was 2.2505pm, but when doped with 4.17% of F it changes to 2.3030pm which indicates a greater stability of the structure concentrations of the dopant above 4.17% reduced the bond length, which made the structure less stable.

STUDY AND ANALYSIS OF ENERGY BANDS WITH VARIOUS TYPES OF CRYSTAL STRUCTURES

The difference between conductors, insulators and semiconductors is to plot the available energies for electrons in the materials. Instead of having discrete energies as in the case of free atoms, the available energy states form bands. Energy bands occur in solids where the discreet energy levels of the individual atoms merge into bands which contain a large number of closely spaced energy levels.

On the combustion heat originating in spin angular momentum that validates the chemical force theory of bonding

Heat generated in combustion reactions, when converted into a vectored force, provides the dynamics for thermodynamics. By combining enthalpy data measured calorimetrically with atomization enthalpies coming out of molecular spectroscopy, it is shown here that the heat liberated during typical hydrocarbon combustion is but the last 25% of the bond-forming potential energy with which free atoms are endowed. In short-lived free atoms, this potential energy is manifest as spin angular momentum. This study introduces a new per-atom theory of chemical bonding based on the chemical force law. Codified in this law is the fact that the intramolecule attractive force exerted by an atom upon its bonded neighbor is directly proportional to the free atom’s spin angular momentum and inversely proportional to the atom’s bonded radius. In the context of the other four fundamental forces maintaining structural integrity in material systems, the chemical force is a lot stronger than the gravitational force, stronger than the van der Waals force, weaker than the electromagnetic force, and a lot weaker than the nuclear strong force. Spin–orbit coupling in the heaviest transition metal atoms enhances the strength of the chemical force. The chemical force law successfully models per-atom chemical bond strengths throughout the periodic table. It also shows that a horizontal Newtonian force F = m(a) originates in atomic spin angular momentum.