JOURNRL OF
Chemical Education: Software Abstracts for Volume 6B, Number 1
or makes an error. Alkimers is menu-driven and includes context sensitive on-line help.
Alkimers
EPR Simulator
Richard R. Hiatt Brock University St. Catharines, Ontario Canada
Miguel A. MartinezJimeno, Carlos Sieiro Depto.Quimica-FisicaAplicada
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Alkimers is a tutorial and nractice vroeram for one of the first problems encountered in Organic Chemistry, isomerism and nomenclature of saturated hvdrocarbons: i.e.. finding the longest chain, determining ihether two differ: entlv written structures are the same wmvound. and finding the total number of isomers for u given formula. Alkimers consists of six moduleri. Three vrescnt thc mlcs of elementary and intermediate nomenclature and isomer construction, while the other three are interactive. The first interactive module displays the isomers of a specified alkane, from methane to decane, and the stuc - c - F - ~ - c - ~ - ~ dent is encouraged to A c e c c guess the number of d isomers before they are displayed. Identify the longest chain shown in this ~h~ second generscreen from Alkimers. Can you name ates a random this alkane? skeleton, displays it, and challenges t h e student to find the longest chain, number it correctly, and name the alkane. This module offers three levels of difficulty: novice, where the longest chain is no greater than eight with no branched substituents; intermediate with carbon chains up to eleven and isopropyl substituents; and expert, where the only limitation is that branched substituents have no more than four carbons. If the student declines to number the longest chain or name the alkane, the nroeram will do so. The nroeram a t t e m ~ t to s analvze anv * . errors and provide meaningful messages as well as the correct answers. The last of the three interactive modules generates six random structures and asks the student to identify those structures that are the same compound. More than one set of duplicates or none a t all may be present among the six. The program identifies the duplicates if the user declines
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Ernesto Brunet Depto. de Quimica Facultad de Ciencias, Universidad Autonorna de Madrid Cantoblanco,28049-Madrid,Spain EPR Simulator simulates the first-order electron paramagnetic resonance spectra (EPR) of up to 12 groups of equivalent nuclei. The program is menu driven and gives a brief explanation for every command. Spectral data are easily introduced and/or modified using a mouse or cursor keys. Further realism can be added to the resulting firstorder spectrum by mixing it with noise a t a specified signal-to-noiseratio. The spectrum can be expanded both horizontally and vertically and changed to a stick plot to facilitate its analysis. Gaussian and/or Lorentzian line shapes are also available. The calculated spectra may he stored for future use or printed. In addition to teaching the basics of EPR to students, EPR Simulator's capability of adding previously created and saved spectra allows the user to simulate complex mixtures of several paramagnetic species with different gfactors and ratios, making it a powerful research tool ( I ) .
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EPR spectrum of n-propyl benzene anion radical from EPR Simula-
tor.
Volume 70 Number 2 February 1993
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