Potential Energy Surface Exploration

One of the most important applications of electronic structure calculations is the exploration of PESs. In particular, the theoretical description of chemical transformations requires the knowledge of the main stationary points of the relevant PESs. 

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Roca, M. Andres, J. Moliner, V. Tunon, I. Bertran, J. On the nature of the transition state in catechol O-methyltransferase. A complementary study based on molecular dynamics and potential energy surface explorations, J. Am. Chem. Soc. 2005, 127, 10648-10655. 

HypcrC. hcm provides calculations IhaL explore molecular potential energy surfaces. Indeed, most of computational chemistry relates in one way or another to molecular potential energy surfaces, the topography of the surface and motion on the surface. 

We are interested in exploring the C3H5F potential energy surface. We will begin hy running optimization and frequency jobs on these three isomers of 1-fluoropropenc... 

We will continue exploring this potential energy surface in Exercise 4.6. 

You can plot the results of the scan to get a picture of the region of the potential energy surface that you ve explored. By doing so, you may be able to determine the approximate location of the minimum energy structure. However, potential energy surfece scans do not include a geometry optimization. 

We ll now use Gaussian s reaction path following facility to explore the H CO potential energy surface. There are many minima on this surface—including... 

In this exercise, you will explore the bond rupture process by performing a potential energy surface scan. Run potential energy surface scans for these molecules, gradually increasing one of the C-H bond lengths, using the specified model chemistries ... 

Here is a plot of the part of the Si2H4 potential energy surface that we ve just explored ... 

One can also explore hov. the other mmimun we noted is located on ihs potential energy surface. Here is a more complete diagram ... 

Computations can be carried out on systems in the gas phase or in solution, and in their ground state or in an excited state. Gaussian can serve as a powerful tool for exploring areas of chemical interest like substituent effects, reaction mechanisms, potential energy surfaces, and excitation energies. 

In highly exothermic reactions such as this, that proceed over deep wells on the potential energy surface, sorting pathways by product state distributions is unlikely to be successful because there are too many opportunities for intramolecular vibrational redistribution to reshuffle energy among the fragments. A similar conclusion is likely as the total number of atoms increases. Therefore, isotopic substitution is a well-suited method for exploration of different pathways in such systems. 

Chemical Reactivity Exploring Potential Energy Surfaces... 

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