Arrhenius equation is a mathematical expression which illustrates the effect of temperature on the rate of a chemical reaction and is used to calculate reaction-rate constants\cite{logan}. In the equation, we have $k$ as the reaction-rate constant, R as the thermodynamic gas constant, A as the pre-exponential factor, E$_a$ as the activation energy and finally $T$ as the absolute temperature. Generally, the equation is represented in exponential form: \begin{equation} k = A \exp[-E_a/RT] \end{equation} It clearly shows that a small increase in temperature would result in a remarkable increase in the magnitude of the reaction-rate constant. The numerical constant A and E$_a$ were derived by collision and transition-state theories of the reactions where E$_a$ represents the energy of activation, measured in kJ mol$^{-1}$. $"A"$ represents the frequency at which atoms react during the chemical reaction and is dimensionless.
Half-life is defined as the amount of time a compound takes to reduce itself to half of it's initial
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Typically, the energy level of stable molecules are low, consequently determining the lowermost energy value of the molecule and attesting the position of the molecule to a stationary point on a potential energy surface(PES) is the primary objective in this step. PES is a mathematical correlation between different molecular geometries and the equivalent single point energies. These values are commonly denoted in a three-dimensional graph in which the bond angle, bond distance and the Hartree-Fock energy value represent the three dimensions of the graph. Geometry optimizations are usually accomplished at the density functional theory(DFT) level as they possess the analytical