lntroductlon t o Spedroscopy, IR, NMR
4 CMR Fred W. Clough, Trinity Software, Sher.
burn Bldg.. Suite 1, P.O. Box 960, Camp ton. NH 03223 IBM PC. PSI2 or Compatible Four Disks (3 in 3.5-in. f m t )and an inswcta's Guide College Level Organic or Instrumental Analysis Class $125
Hardware: Components:
Level and Sublect: Cost:
1
Summary Ratlng.: Category Ease d On; Sub~IManw Cmfent: PedagogIlc vaim: Sludent Rsadlm:
Good Excellent Good
Excellent
This is a set of programs designed to help students learn w analyze and interpret infrared.:H-NMRand "C-NMR spectra. It is available for IRM PC. PSI2 or 100% eompatible computers with a t least 256K,CGA and compatible monitor and DOS 2.1 or higher. The programs will work on a computer which has either one or two floppy disk drives and/or a hard drive. The puhlisher permits the making of one backup copy and installation on a hard disk. There is a ane-year warranty an the disks and a 30day period during which you may return the disks for afullrefund ifvou are not satisfied. Registered owners receive free upgrades and wchniral support if needed. Fach of the three proflams would serve well as either an introduction to spectral interpretation or as a review and would be entirely appropriate for students in Organic
or Instrumental ehemistrv. The entire svstem is menu-driven and each of the major
topics (IR. 'H-NMR, 'C-NMR) hegins with a section which gives general instructions describing the keys which are used for responges and permits the user to turn off the sound associated with correct and incorrect responses. The first-time user can then work throueh each of the menus and submenus in order:'~hegoal is to rearh a point where he or she can interpret a spectrum, i.e., either identify the molecule or the functional groups responsible for the displayed spectrum. Background information is available as a set of menu items. These describe topics such as the nature of the transitions, relaxation mechanisms.. samole and . .oreuaration . solvents, instrument configuration, spinspin splitting, intensities, and integration. Generally. the purpose is to provide abackground that will give an understanding of the origin of the spectra and contribute to the interpretation of spectra of unknowns. The analysis of IR spectra begins by identifying six important regions in the spectrum and 23 functional groups primarily responsible for the bands in these areas. This is nicely emphasized by animating the particular vibrational mode while simultaneously displaying a characteristic hand in a spectrum. A quiz can follow the description of each area. These quizzes are randomly generated and display a hand in a spectrum and ask the user to identifv the functional group. There could he improved by choosing the questions randomly but preventing repetitron. The quizzes are well-designed though and involve review of spectral areas already described, if they are studied in order. I t would be easier to respond in these quizzes if the major wavenumber tic marks were Larger. There is also a quiz that reviews all six areas. In addition. vou can review spertra for each of the funnional groups by ~rhservmgcomplete spectra w ~ t hcorrohoratiug bands highlighted.
Another series of quiz questions asks the user to input functional group names based on the presence or absence of peaks in the displayed spectrum. This is one place where the help key (Fl) is active, but ifthey key is pressed in response to the screen prompt, the list of acceptable responses does not appear. The user is instead returned to a higher level menu and vou have to start over. This is annoying. The finalsection is the 1R test. In this well-presented section the student enter* a list of functional groups posaibly present in a compound for which the spectrum is displayed. The groups actually present are then listed and the peaks that are responsible for them are highlighted. In general, the methods used to develop skills in interpretation of the two types of magnetic resonance spectra are similar to those described above. After working through the modules which give background information and quizzes on these topics the students can elect to practice by doing a computer-assisted interpretation of a 'HNMR spectrum, far example. In this module the student is euided throueh an interoretation. a spectrum is displayed and an important IR hand is identified. Thestudent then responds to queations that are intermixed with discussions about degree of unsaturation, chemical shifts, etc., until an interpretation is determined. The final test on 'HNMR is very good. There are 40 unknowns (which could be assigned as problems) that can he chosen. Both the IR and 'H-NMR spectra are shown along with the molecular formula. The student then constructs a structural representation of the suspected compound using a simplq input process. Hints are available if they are needed. Analysis of W-NMR spectra is approached in two ways. The student can predict the details of a soectrum based on a structure. Alternatively, both the proton noise decoupled spectrum and the proton off-resonance decoupled spectrum for a compound are displayed. The student then responds to que-
--Reviewed in This Issue
Computer Learning Packages Fred W. Clough, Introduction to Spectroscopy. IR, NMR, and CMR ASYSTANT
James E. Byrd
A194
AJay Shah and S. Lakshmi Ramaralu
A195
Daniel T. Haworth George B. Kauffman
A196 A196
Books
James E. Brady, General Chemistry: Principles and Structure Nickolaos A. Peppas, editor. One Hundred Years of Chemical Engineering: From Lewis M. Norton (M.I.T.) to Present Titles of interest
A194
Journal of Chemlcal Education
ries directed a t identifying a structure consistent with the soeetrauresented. Ifelt that thlisertionaasiot dev;lopedas thoroughly as the other two. A final module directed toward rdentrfication of unknowns for which all three spectra were presented would have been welcome to give additional practice in interpretation of spectra. We have had an opportunity to use this in our Instrumental Analysis course where the instructor assigned the IR section in place of an introductory lecture. The students felt that it was an excellent introduction and that it helped them significantly in their analysis of unknown sample spectra. Other than the problem with the help (Fl) key noted above, they had no difficulty using the software. The students used the orogram wlthout seeing the manual and reported no instances uf the program crrtshing. By breaking the topic up into so many nuhtopics they could easily return to the program after leaving it, without unnecessary repetition. I t should he pointed out that the user is asked to enter a response via the return key, hut the space har has the same effect and it is more convenient. We did not encounter any errors in content and, considering the amount of text presented, the two or three typographical errors were only slightly distracting. Program execution, on an 80286 based computer with a bard drive, was sufficiently fast that delays were not noticeable. These programs are so easy to use that no additional exolanation is necessarv. The manual that romea wrththedisks inrludrsa procedure for rnstdling the prugrams. The mstnrrtlons were easy to follow and the Installation procedure worked exactly as described. The manual also includes a brief description of each of the topics covered and a list of the 40 compounds used as 'H NMR unknowns. James E. Byrd Callfornla State Unlversily. Stanislaus Turlock, CA 95380
ASYSTANT ASYST Software Technologies, Inc., 100 Corporate Woods. Rochester, NY 14623 Hardware:
Components: Level and Subject: cost:
IBM PC XTlAT or 100% compatible with Math Coprocessor and hard disk Soflware and Manuals Advanced undergraduate. graduate laboratory course and hard disk $495
Summary Ratlngs: Category Ease of Use: Subrnl Mallw CmMnf: P e d o ~ p ~Value: Ic Sludenl Rsacllon:
E~osllent Gwd Average Good
L
The scientific number crunching package Asystant by Asyst Software Technologies, Ine. is a powerful mathematical and statistical analysis software tool. I t is designed to meet research needs of scientists and engineers. Asvstant reouires verv little eomouter bark,qround. However, in ordcr to exploit all its rnpahilitier the user must be profi-
cient in differential and integral calculus. advanced matrix algebra, and waveform analysis. This product is not intended to be an instructional software package. However, it will find its usefulness in graduate courses in Quantum Mechanics, Physical Chemistry, Chemical Physics, Inorganic Chemistry, and Phvsics. I t mav be used to circumvent complex mathematical procedures, thus enabling the students to concentrate on the ronrepts of rhemistry. Asyrlont will be mostly useful in advanced laboratory courses and analysis of research data. The Asystont package comes with a very well organized and easy to comprehend tutorial and reference manuals. The tutorial manual is divided inta seven chapters. These chapters guide the users through various features of Asystant. Agystont does have an ereellent context sensitive help. However, it does not contain a disk-based tutorial, which we believe, would havegreatly enhanced learning. Asystont is fully menu driven. The menu system is divided inta two, the main menu and the secondary menu. You may toggle between the two menus by using (PgUpl and (PgDnJkeys. The main menu offers graphics, polynomial analysis, waveform generator and processor, differential equation solver, curve fitting, and statistical analysis capabilities. Asystant has excellent graphic features. Its graphics capabilities include cartesian -xy and logarithmic plots of one- or twodimensional arrays as well as axonometric and contour plots of two-dimensional array. However, polar plots are not available. Graphs may be manipulated several ways. For example, x and y axes may be automaticallv scaled or manuallv soecified. Window sizes mav he adiusted. Grid.. oriein..~and labels mny be specified. Aaonometrir plot menu includes uptiuna for amplitudp compression factor, horizontal shift, and vertical hase fraction. Asystont can display up to nine windows simultaneously, which makes it easier to compare different sets of experimental and research data. The absence of VGA suooort limits on-screen maohics resolution.?he graphics output may be directed to one of several supported printers or plotters. Asystont cannot read Lotus 123 Nes directly, but, an ASCII file or a DIF file may be converted to Agvstont subfile using the File I10 feature of the main menu. A comprehensive set of pnredures built into the file processor allows the user to process large and multrple data rets aummatically and assign them to various arrays or files. Two polynomials can be added, suhtracted, multiplied, and divided. Asystant can integrate, differentiate, and find roots of polynomials as well. However, the most impressive feature is its ability to generate Legendre, Laguerre, Tchebyshev, and Hermite polynomials. Although, polynomials of only up to 10th degree may he processed. The main menu also offers an Ordinary Differential Equations (ODE) solver. ODE's of up to fifth order can be solved, and the results may be displayed graphically. First order ODE's mav be solved verv easilv. .. alrhough, wiving higher order O L require ~ substantial knowledge of differential calculus. Asystant can fit linear, polynomial, loga~
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rithmic, exponential, multilinear, and userdefined functions. The user-defined functions mav he fitted usinn one of the three ~, available algorithms. rin., Gaurs Newton, BFtiS, and hybrid of the two. Although a predefined cubic spline rurve-fitting function is not available. A very good statistical analysis package is built into Asystant. Once the data set is provided in the form of an array, sum, mean, median, sample variance, standard deviation, skewness, kurtosis, sum of squares, and rms may he computed. More advanced features like hypothesis test, ANOVA and regression analysis may also be computed with ease. Asystant is among few equation solving packages that also incorporate a fairly soohistieated waveform eenerator and calculator. As)atonl isan analog funrtiongenerator with pnrviaions for waveform type.gain, bias, and frequencv rontrols. Various wareforms, sine, cosine, square, etc., may be generated. Also, uniform and normal noise distribution may he generated. The waveform calculator acts on a one-dimensional array and has an ability of displaying the results in a graphical fashion. A waveform may be split into several segments and may be worked on separately. The waveform processor in the main menu incorporates two primary options, processing and analysis. Using the process menu user can smooth a waveform and generate its derivative and integral waveforms. Asystant also calculates the power spectrum using Fast Fourier transform (FFT) and envelop of the spectrum using Hilbert transform techniques. The analysis option enables the calculation of basic statistical data (like mean, sd, rms, etc.), peak width, area under the curve, rise time, and fall time. The secondary menu is organized into four submenus. All the secondary menu functions work on stack contents. The four submenus are accessible by the next command on the top of the secondary menu. These suhmenus offer a scientific calculator, an array manipulator, a special functions calculator, and a matrix and waveform analyzer. The first of the secondary menus is an excellent scientific calculator with trigonometric and logarithmic functions. This calculator works on a RPN (Reverse Polish Notation) Logic like any H P calculator. Althoughany computation followed by a slash (0forces a regular calculator mode. Numbers or arrays are entered in stacks and various ooerations are oerformed on the stacks top down These stacks may be eas~lyman~pulatedurmg functrunr lcke swap and roll Array operations menu (one of the secondary menus) lets user create and manipulate arrays. Two arrays may be added, subtracted, and multiplied. This menu also provides array transpose, reshape, sort, and search facilities. The conversions and special functions submenu is extremely-useful for advanced mathematical operations. Cartesian and spherical coordinates can he interconverted. A complex number may he represented in polar or rectangular form, conversion of one representation to another may be easily carried out. Asystant can compute complex conjugate, modulo, permutations, and com(Continued on page A1961 ~~~~~~
Volume 67
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Number 7
July 1990
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