Physical chemistry courses computation

But, we expect that the majority of readers will be those with only a rudimentary command of quantum chemistry and chemical bonding theory (e.g., at the level of junior-year physical chemistry course) who wish to learn more about the emerging ab initio and density-functional view of molecular and supramolecular interactions. While this is not a textbook in quantum chemistry per se, we believe that the book can serve as a supplement both in upper-level undergraduate courses and in graduate courses on modern computational chemistry and bonding theory. 

Computational chemistry is essential in a modem physical chemistry course. One approach would be to use laboratory time to have students work through a number of exercises accompanied by elaboration of the concepts in lecture or pre-laboratory discussions. Each of die major computational chemistry software packages come with workbooks or tutorials for learning the software. For example, students can learn by completing exercises in the Spartan tutorials (57). Similar approaches can be taken when using Gaussian (38) and Hyperchem (39) tutorial or exercise collections. 

The growth of computational chemistry and the ready availability of commercial ab initio packages has had a dramatic effect on the way that physical chemistry is practiced in the contemporary research laboratory. The clear implication is that without integration of computational chemistry into our physical chemistry laboratory curriculum we will be failing to teach our students how contemporary research is conducted. Fortunately, a number of approaches to including computational chemistry in the physical chemistry laboratory have been developed. These range from modifications of the full course to individual computational chemistry exercises for the laboratory. These developments can be found in Table VII. 

Two papers reported powder pattern crystallographic results. The paper by Santos et al. (7) stood out from the rest because it presented a collection of more classical physical chemistry experiments. In this paper the authors described the use of micro-combustion calorimetry, Knudsen effusion to determine enthalpy of sublimation, differential scanning calorimetry, X-ray diffraction, and computed entropies. While this paper may provide some justification for including bomb calorimetry and Knudsen cell experiments in student laboratories, the use of differential scanning calorimetry and x-ray diffraction also are alternatives that would make for a crowded curriculum. Thus, how can we choose content for the first physical chemistiy course that shows the currency of the discipline while maintaining the goal to teach the fundamentals and standard techniques as well ... 

Computational methods are of increasing importance in the chemical sciences. This paper describes a computational chemistry laboratory course that has been developed and implemented at the University of Michigan as part of the core physical chemistry curriculum. This laboratory course introduces students to the principle methods of computational chemistry and uses these methods to explore and visualize simple chemical problems. 

The prerequisites for the course include two years of chemistry, including organic, analytical, and an introductory inorganic chemistry course, one year of calculus-based physics, three terms of calculus, and introduction to differential equations usually taken concurrently. Most students take the computational laboratory concurrent with the physical chemistry lecture course covering... 

By the late 20th century, continued calls for the revision of the physical chemistry curriculum were being heard (2-8). These calls were for a significant modernization of both the lecture and laboratory curriculum involving an inclusion of modem research topics into the lecture and the laboratory, the deletion or movement of selected material into other courses, and a reduction in the writing requirements for the laboratory. More specifically, the need for experiments and discussion relating to the incorporation of laser and computer technology has intensified with the spread of these devices into all the chemistry subdisciplines. The ACS published a selection of modernized experiments in an earlier volume (5). 

Physical chemistry is an upper-level course at most institutions and is generally only required for a few majors. As such, course enrollment is at least an order of magnitude below that of general chemistry, and sometimes much less. Thus, physical chemistry, and its associated laboratory component, where offered, have a small enough enrollment that it can be hard to justify the cost of specialized instrumentation such as spectrometers, lasers, computer controls, and other such equipment... 

There are five chapters in Part I Introduction to quantum theory, The electronic structure of atoms, Covalent bonding in molecules, Chemical bonding in condensed phases and Computational chemistry. Since most of the contents of these chapters are covered in popular texts for courses in physical chemistry, quantum chemistry and structural chemistry, it can be safely assumed that readers of this book have some acquaintance with such topics. Consequently, many sections may be viewed as convenient summaries and frequently mathematical formulas are given without derivation. 

A theory also serves as a scientific model. A model can be a physical model made of wood or plastic, a computer program that simulates events in nature, a mathematical model or simply a mental picture of an idea. A model illustrates a theory and explains nature. In your chemistry course, you will develop a mental (and maybe a physical) model of the atom and its behavior. Outside of science, the word theory is often used to describe someone s unproven notion about something. In science, theory means much more. It is a thoroughly tested explanation of things and events observed in nature. 

No excuses. Anyone who has passed a course in physical chemistry should be able to crunch this book for numbers and for equations. Engineers can treat it as a handbook with long explanations whose formulae can be plugged into original programs or packaged software (preferably both so as to understand what is being computed). 

This too is changing. There have long been courses on advanced physical chemistry, which included quantum mechanics, and on physical organic chemistry. These and introductory courses are being redesigned to include topics in computational chemistry and molecular modeling at colleges and universities. ... 

Our aim in this chapter will be to establish the basic elements of those quantum mechanical methods that are most widely used in molecular modelling. We shall assume some familiarity with the elementary concepts of quantum mechanics as found in most general physical chemistry textbooks, but little else other than some basic mathematics (see Section 1.10). There are also many excellent introductory texts to quantum mechanics. In Chapter 3 we then build upon this chapter and consider more advanced concepts. Quantum mechanics does, of course, predate the first computers by many years, and it is a tribute to the pioneers in the field that so many of the methods in common use today are based upon their efforts. The early applications were restricted to atomic, diatomic or highly symmetrical systems which could be solved by hand. The development of quantum mechanical techniques that are more generally applicable and that can be implemented on a computer (thereby eliminating the need for much laborious hand calculation) means that quantum mechanics can now be used to perform calculations on molecular systems of real, practical interest. Quantum mechanics explicitly represents the electrons in a calculation, and so it is possible to derive properties that depend upon the electronic distribution and, in particular, to investigate chemical reactions in which bonds are broken and formed. These qualities, which differentiate quantum mechanics from the empirical force field methods described in Qiapter 4, will be emphasised in our discussion of typical applications. 

Students at the University of South Alabama are currently introduced to computational methods in a five credit hour special topics course. The course meets for four hours of lecture and three hours of laboratory for each week of a 10-week quarter term. This course is designed for students who have completed three terms (quarters) of physical chemistry, so that all the students have had some exposure to quantum chemistry. The object of the course is to expose the student to a wide variety of computational tools that can be used to solve various chemical problems. 

This case study will describe the use of computers in the undergraduate quantum chemistry course at two levels. The first level uses the computer to solve routine, small-scale quantum mechanical problems on a day-to-day basis. These are the kind of problems that appear at the back of the chapter in physical chemistry or quantum chemistry texts, or in compilations of quantum mechanical exercises. The current generation of students generally attack these problems with hand-held calculators of various levels of computational sophistication. Earlier generations struggled with slide rules, math tables, and mechanical calculators. 

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