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Transition state theory explains the dynamics of reactions. The theory is based on the idea that there is an equilibrium between the activated complex and reactant molecules. The theory incorporates concepts from collision theory, which states that for a reaction to occur, reacting molecules must collide with a minimum energy and correct ...
This theory was developed simultaneously in 1935 by Henry Eyring, then at Princeton University, and by Meredith Gwynne Evans and Michael Polanyi of the University of Manchester. [3] [4] [5] TST is also referred to as "activated-complex theory", "absolute-rate theory", and "theory of absolute reaction rates". [6]
The concept of a transition state has been important in many theories of the rates at which chemical reactions occur. This started with the transition state theory (also referred to as the activated complex theory), developed independently in 1935 by Eyring, Evans and Polanyi, and introduced basic concepts in chemical kinetics that are still used today.
The process of chemical reaction can be considered as involving the diffusion of reactants until they encounter each other in the right stoichiometry and form an activated complex which can form the product species. The observed rate of chemical reactions is, generally speaking, the rate of the slowest or "rate determining" step.
In chemical kinetics, the entropy of activation of a reaction is one of the two parameters (along with the enthalpy of activation) that are typically obtained from the temperature dependence of a reaction rate constant, when these data are analyzed using the Eyring equation of the transition state theory.
An example of a simple chain reaction is the thermal decomposition of acetaldehyde (CH 3 CHO) to methane (CH 4) and carbon monoxide (CO). The experimental reaction order is 3/2, [4] which can be explained by a Rice-Herzfeld mechanism. [5] This reaction mechanism for acetaldehyde has 4 steps with rate equations for each step :
Complexity theory is also being used to better understand new ways of doing project management, as traditional models have been found lacking to current challenges. [ 19 ] : 23 This approaches advocates forming a "culture of trust" that "welcomes outsiders, embraces new ideas, and promotes cooperation."
Behavioral systems analysis is an approach to organizational design and management. It is based on the premise that organizations are complex systems.As such, changes in one aspect of performance in an organization necessarily affects performance in another parts of an organization.