Software: Calculating Empirical Formuals

Software. Calculating Empirical Formulas. MS Calculator. SoftShell. 1600 Ute Ave. Grand Junction, CO 81501-4614. 970-242-7502; fax 970-242-6469; info@...
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Software

Calculating Empirical Formulas System requirements

MS Calculator SoftShell 1600 Ute Ave. Grand Junction, CO 81501-4614 970-242-7502; fax 970-242-6469; info@softshell. com; http://www. softshell. com $149 industry, $99 govemment/academia, $29 student

MS Calculator provides the mass spectrometrist with a compact electronic window on either a PC or Macintosh computer to calculate a list of all possible empirical formulae or the empirical formulae and radical ion compositions of an entered molecular weight. It supports high-resolution data and provides an adjustable table of exact masses for many elements. Other elements can be easily added to this table. In addition to entering a mass and a mass tolerance, numerous other constraints, such as the number of atoms and mass percent of an element and the number of double-bond equivalents, can be placed on the generated list of formulae. Once a list of all possible empirical formulae is generated, it can be sorted by mass, element, mass percent of an element, or double-bond equivalents. This capability is of obvious importance for any mass spectrometrist who needs to assign empirical formulae to MS data, and it results in considerable time savings compared with calculating these values manually. 484 A

MS Calculator can be run on either a PC or a Macintosh. For a PC, it requires Windows 3.1 or higher, 2 MB RAM, and 281 KB of hard-disk space. For Macintosh systems, MS Calculator requires a Mac System 6 or higher and 1 MB RAM. No CPU requirements have been specified. We have evaluated this program only on a 486/DX2-66 PC with 8 MB RAM, so we cannot attest to its performance on other systems. Installation, support, and documentation

MS Calculator is installed through Windows in the same manner as other Windows-based programs. Thus, anyone familiar with installing Windows-based programs should be able to install it without consulting the documentation. Use and operation of the program itself is straightforward and intuitive. The documentation and online help more than

adequately explain how the program works. We also found that the technical support from SoftShell is excellent. Overall, we did not experience any problems with either installing or using this program. Using MS

Calculator

One of the best features of MS Calculator is that it can run on both PCs and Macintosh computers, unlike the majority of similar programs that typically run only on more sophisticated computer hardware. This feature allows scientists to interpret their mass spectral data in the office, at home, or on any available computer running MS Calculator rather than only on the computer attached to the mass spectrometer. This capacity also facilitates the production of reports because the list of formulae can be copied and pasted into other programs, such as word processors or other Windows applications.

MS Calculator calculates a list of possible empirical formulae based on an entered molecular weight.

Analytical Chemistry News & Features, August 1, 1996

However, when one uses the key SOFTWARE RELEASED provided by the program, the entire list of possible formulae is copied and subse- KaleidaGraph quently pasted to other applications. If Synergy Software you want only a range of formulae or an 2457 Perkiomen Ave. individual formula to discuss in another Reading, PA 19606 application, you must truncate the 610-779-0522; fax 610-370-0548; pasted list from inside the other maxwell@sales. synergy, com application. Version 3.0; $249 Another highlight of this program is that it does not generate as many nonsen- KaleidaGraph provides data analysis and sical chemical formulae as do other simigraphing in both the Macintosh and Winlar programs. In particular, the list of emdows environments. Plots can be conpirical formulae generated excludes comstructed in line, scatter, double-Y, high/ positions that violate the nitrogen rule, as low, probability, x-y probability, stack histowell as compositions with hypervalent gram, box, percentile, horizontal bar, atoms. We are unaware of other programs column, stack column, polar, and pie types. with this capability. Features include built-in curve fitting, plot Despite the general utility of MS Cal- customization, drawing tools, statistics, and simplified data management. The Windows culator, this program appears to have a few minor weaknesses. For example, MS version runs under Windows 3.1, Windows 95, Windows for Workgroups 3.11, and Calculator lists the empirical formulae based on the selected parameter, that is, Windows NT and requires an 80386 or higher processor, 6 MB RAM, and 2.5 MB mass, number of atoms from a specified of free hard-disk space. The Macintosh verelement, and so forth. It would be useful sion runs on any Macintosh with System if the list could also be ranked by the 6.0.5 or later and 2 MB RAM. deviation from the input molecular weight. Unscrambler Although it would also be helpful if MS Calculator could calculate the molec- SciOptics ular weight of an input chemical, this 7226 W. Colonial Drive, # 309 function can be found in a different SoftOrlando, FL 32818 Shell program (M. M. Calculator), which 407-292-3168; fax 407-292-3169; is supplied with SoftShell's chemistry quanta@scioptics. com; drawing packages (ChemWindows and http://www.scioptics.com/~quanta/ Chemlntosh). Finally, it would be useful Version 6.1; $4500 if the exact masses of the calculated formulae were included in the list. Unscrambler multivariate analysis software runs under Windows 95, Windows Despite these minor inconveniences, we believe that MS Calculator is a useful for Workgroups 3.11, and Windows NT. Features include traditional statistics, time-saving tool for the interpretation of principle component analysis and regresEI mass spectra. Reviewed by Adam Brockman and Ron sion, partial least-squares and multiple linear regression, response surface analyOrlando, Complex Carbohydrate Research Center, Departments of Biochemistry and sis for design optimization, analysis of Molecular Biology, University of Georgia,variance for analysis of designed data sets, and SIMCA classification. Athens

Chemistry Solver New Light Industries 9713 W. Sunset Hwy. Spokane, WA 99204 509-456-8321; fax 509-456-8351; nli@comtch. iea.com; http;//www. iea.-com/~ nli Version 1; $375

Chemistry Solver is designed to solve complex problems on which a trial-and-error approach might be used, such as balancing complex equations, curve fitting, building mathematical models from empirical data, improving reaction efficiency, solving coupled sets of nonlinear partial differential equations, and training neural networks. Based on genetic algorithms, Chemistry Solver uses data from an Excel spreadsheet to find the optimal solution to the problem. System requirements include a PC with at least a 386 processor, 2 MB RAM, Windows 3.1 or Windows 95, and Microsoft Excel. Bookends Web Westing Software 134 Redwood Ave. Corte Madera, CA 94925 415-945-3870; fax 945-3877; westing3@aol. com $179

Bookends Web is a bibliography/reference management program that incorporates World Wide Web capabilities. References can be formatted in HTML and pasted into home page documents. Bookends Web databases can be searched from a Web page form over the Internet, and formatted references can be retrieved. Hypertext links to abstracts or the full article can be included as well. System requirements include a Macintosh with at least 4 MB RAM, a hard disk with at least 2.5 MB free, System 7 or later software, and Webserver software.

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