We trolled the internet in search of freeware geochemistry programs. All but a few of the programs listed below are free; others are shareware, payware or partial-ware (also called cripple-ware, but we don't like that word). We stayed away from such superstars as PHREEQC and MELTS.
If we had a nickel for every electronic periodic table, we could start our own geochemistry journal and our papers would never be rejected. Similarly common are more or less useful plotting routines, countless unit converters and hundreds of GIS mapping packages. Surprisingly few geochemistry programs are flexible enough to serve more than a small subset of our science. Programs that are adjustable enough to serve multiple specialties are extravagantly overpriced. Priced Aquachem® lately?
We hope that some of the programs are useful to some of you. If you know of useful but perhaps obscure freeware that will help more than one segment of our Society, please send us the URLs. We will publish another software collection when the suggestions reach a critical mass.
|Periodic Table Explorer (PTE)|
The most complete, informative and elegant periodic table we've seen. Aside from the usual nuclear information, PTE includes: numerical, graphical and animated electron orbitals; brief YouTube movies about elements; electronegativities; isotopic abundances and half-lives; important compounds and reactions; electromagnetic spectra; melting points; densities; elastic properties; production methods; biographies of discoverers; and on and on. No ads, no broken links, no WWW hassles.
|Interactive Chart of the Nuclides|
The General Electric Company published the First Edition of the Chart of the Nuclides in 1948. The 16th Edition (2002) is available at www.ChartOfTheNuclides.com ($25.00). It is 1.3 meters by 0.9 meters and comes with a 48-page booklet that explains decay mode. Only the wall chart conveys the sheer majesty nuclide array. On the other hand, it is hardly portable. The National Nuclear Data Center's online version is convenient and, at this writing, some constants were updated on December 2, 2008. Turn off the Tooltips to speed up the table response. Try the fast Java version here.
|Earth's Core |
This program aspires to be an electronic version of The Rock-Forming Minerals (Deer, Howie and Zussman, 1992). It compiles mineral photographs, crystal systems and habits, and locations of major deposits minerals, rocks and gems. The mineral database, glossary of geochemical terminology, and selected biographies are satisfyingly informative. (Quick, what is schmitterite? Uuranyl tellurite, of course. Did you know that "oil of vitriol" is a synonym for sulfuric acid?). The program is a beta version. But geochemists will like it even in its diamond-in-the rough form.
This program has two parts: Perhaps 80% of the program is akin to a highly condescended version of the (Chemical Rubber Company) CRC hand book. This part has numerous entries of interest to geochemists. However, it is no match for the CRC, and the reference list does not contain page numbers for the data from each source. I wouldn't feel comfortable referencing Chemtoolbox in a journal article.
|Geochemical Data Toolkit (GCDkit)|
A program for analyzing and plotting whole-rock compositions. The text that describes this program is #1 in the Journal of Petrology's download list. Puzzleing. The program calculates several types of normative compositions (e.g. Niggli, CIPW, Barth's catanorm); saturation indices for apatite and zircon; and REE transformations. Here too are statistical tools and common petrologic graphs: AFM diagrams, graphs for determining tectonic setting from trace element compositions, etc. The plots are difficult to edit and not of publication quality. Use GCDkit for a first-pass data overview and to calculate normative compositions. Import the results into a different program for plotting. Excel macros are available for many of the GCDkit plots routines.
|Chemical Equation Expert|
Balance an equation the old-fashioned way?
1. Balance elements other than O and H. Add coefficients as necessary. 2. Add water to balance oxygen. 3. Balance hydrogen. 4. If the equation doesn't balance or make physical sense, start over.
Balance an equation with Chemical Equation Expert?
|CRONUS (Cosmic-Ray Produced Nuclide Systematics on Earth Project)|
Use these programs to calculate rock exposure ages and surface erosion ages from 10Be and 26Al isotope concentrations in quartz. Concentrations are from measurements of10Be/9Be and 26Al/27Al by accelerator mass spectrometry. If your work involves these data, you already know about the programs. For the rest of us, it is instructive to go through the documentation and calculate exposure and erosion ages from test data. The plot shows exposure ages for a glacial erratic on Martha's Vineyard. Circles are from 10Be; triangles from 26Al; line lengths are uncertainties; and colors are results from different assumptions about 10Be and 26Al spallation rates.
Simulates the evolution of unicellular organisms. It models mutation, genetics, photosynthesis carbon and oxygen cycles, and growth-limiting factors in ecosystems. Organisms are color keyed. Their offspring have the same color but may mutate to better- or maladapted forms. The better-adapted cells reproduce whereas maladapted forms die out. Metabolism and available nutrients are incorpated into the similations. Even better-adapted mutated cells may die before they reproduce if they starve. All in all, the simulation is a great learning tool, and dare we say it, fun.
The Fact-Web applications are free examples of the huge FactSage thermochemical database and program collection. A complete "Thermodymacs in Geology" course be designed around the Fact-Web. At right is the "PhaseDiagram-Web". First, take in the overall aspect of the diagrams with its cascading peritectics. To a certain type of geek, who shall remain nameless, its beautiful. Now write the reactants, products and reactions at each peritectic and the eutectic. Check your answers by typing a temperature in the lower left box; the program returns he equilibrium phase assemblage. Lucky you; there are 19 more binary phase diagrams to decipher.
Simulates crystal growth from first-order thermodynamic principles and Monte Carlo random numbers. Thermal activation reactions define the probabilities that liquids or gases will condense at crystal faces. Comparison of these probabilities to random numbers determines whether new molecules precipitate or dissolve at the topmost crystal layer. User inputs include: the current liquid temperature, the crystal melting temperature, the liquidus temperature, and the fraction of liquid in the crystal-liquid mixture. Graphs and simulated images show changes in the crystal growth rate, roughness of the topmost crystal layer, and changes in total crystal thickness. The program continuously updates and displays enthalpies, frequencies of molecular transitions from non-condensed phases into the crystal, activation energies and other variables. Leocrystal is instructive about high-temperature crystal-liquid systems at the molecular level. In geochemical terms, it helps clarify crystal-liquid interactions at temperatures appropriate for rhyolites through komatiites.