Fourier transform NMR simulations - Journal of Chemical Education

Harold M. Bell. J. Chem. Educ. , 1993, 70 (12), p 996. DOI: 10.1021/ed070p996. Publication Date: December 1993. Cite this:J. Chem. Educ. 70, 12, XXX-X...
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Figure 11. Transformedspectrum before phase correction.

Figure 10. Two second display of noisy FID. The program will be provided at no charge to anyone sending a dlsk and prepaid mailer, otherwise the cost is $5.00. Checks should he made oavablc to the Vireinia Tech Chemistry Department and s i n i t o H. M. Hell, chemistry 1)euartment. Vireinia l'ech. Hlackshure. VA 24061. Unless an'alternate con%guration'is specifiei,' the program provided will require VGA graphics and a n 8087 math coprocessor. Versions that will run on CGA and EGA, with or without the 8087, can be supplied upon request. A text file that contains a tutorial session with 20 suggested exercises will also be provided.

Raw Data to Finished Report: Microcomputer Assisted Estel D. sprague3 University of Cincinnati Cincinnati. OH 45221-0172

The integration of microcomputer use into our undergraduate program has received increasing emphasis in recent years. The focus of that emphasis is a junior-year course, the theme of which is accurately reflected in the title given above. Microcomputing applications in the first two years of our program have consisted of the use of drilland-practice software and computerized pre-lab quizzes for freshmen. Although plans for more extensive applications at this level are now being formulated, especially for the laboratow profram, truly substantial use of microcomputers presentiy begins in the first quarter of the junior vear in the course to be described here. Phvsical-Analvtical Measurements. This is a 3-credit, reqGred course, designed to prepare our students for other courses to follow. Its principal goal is to train our chemistry majors to view and make use of microcomputers just as professional chemists do: as ordinary, everyday tools, to be employed routinely, rather than just in special situations. Course Content Course content can be divided into four areas.. uursued more or less simultaneously as the quarter progresses: general mechanics of computer use, data and uncertainty

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3~resentedat tne 1991 Comp~tersIn Cnem ca Ed~caton Workmop. Case Western Reserve U n versry, Cleve ana, OH. 'Since the methods and procedures being taught, rather than specific software packages, are the principal concern in this course, the students are permitted to use any high-qualitysoftware which may be available to them. The maioritv use the student edition of Lotus 1-2-3 and Wordperfect,although several other packages are also used.

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Figure 12. Transformed spectrum after phasing and expanding. analysis, spreadsheet operations, and report writing. Materials used include the error analvsis text bv Tavlor (12). spreadsheet and word-processing~so~ware~ an: nonlin: ear, least-squares software (13). Some instruction in the routine mechanics of microcomputer use remains necessary, since a preliminary survey each year continues to reveal a significant fraction of our students with minimal prior experience. A little time is spent describing the internal workings of microcomputers and, especially, the care and use of floppy disks. Although students are increasingly likely to have access to computers at home or a t part-time workulaces. manv still carrv out much of their work in a departmental computer lad. Thus. some instruction is necessarv concernine the lavout and i s e of the computers, laser priiters, and other dehces in this facility. Touics in the analvsis of data and their associated uncer~~~~~tainiies are organized aroudd the book by Taylor. We cover much of this text by means of lectures, problem sets, and reading assignments, going substantially beyond the text in the area of model-fitting calculations. In particular, we discuss and make use of model evaluation methods described earlier in this Journal (13).Required, in general, are nonlinear, least-squares calculations, where emphasis is placed on the often misunderstood fact that it is nonlinearity in the adjustable parameters, ruther than in the experimental variables. to which reference is made. Thc simplification in error analysis resulting from the use of such methods is also pointed out as an added benefit. Spreadsheet procedures are covered in detail in lecture, illustrated by means of a portable computer and liquid crystal overhead display panel (as are all specific computer manipulations). Over a period of several weeks many of the typical business-oriented exercises found in the manuals accompanying such software, extended with appmpriate chemistry examples, are assigned as homework. The students are required to become reasonably proficient in using essentially all of the capabilities of the spreadsheet software except for macros, which we have not found time or need to include formally. Since regression analysis is carried out easily in most spreadsheet software packages,

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Volume 70 Number 12 December 1993

997