Date of Award
Doctor of Philosophy
Theresa L. Windus
The current document includes six chapters, which are published, accepted, or prepared for submission in various journals. Chapter 2 introduces a study on the triplet surface of O+C2H4. Chapter 3 presents a study on the singlet and triplet surfaces of O+C2H4 with a focus on biradical species. Chapter 4 continues the previous study with a more extensive study on the energetically lowest-lying singlet surface of O+C2H4. Chapters 2-4 rely on a several multireference methods to model ground and excited states and on some single-reference methods. Chapter 5 presents a multireference study on SiCH4 and butadiene with ORMAS energy, first-order nuclear derivative, and first-order nuclear derivative coupling contours, which characterize whether or not the ORMAS approximation effects correct analytical derivatives with seemingly smooth energies over a range of geometries. Chapter 6 presents the interface of NEWTON-X (a dynamics driver program) and GAMESS (an electronic structure suite) along with a dynamics study on CNH4+ that demonstrates the possible effects of the ORMAS approximation on product distributions.
Aaron Carl West
West, Aaron Carl, "Too continuous to continue? Multiple electronic surfaces and derivatives" (2012). Graduate Theses and Dissertations. 12967.