Copyright Status of Thermodynamic Properties?
orzetto writes "I work at a research institute, and programming models of physical systems is what I do most of the time. One significant problem when modeling physical processes is finding thermodynamic data. There are some commercial solutions, but these can be quite expensive, and to the best of my knowledge there are no open source efforts in this direction. In my previous job, my company used NIST's Supertrapp, which is not really that expensive, but is written in Fortran, and an old-fashioned dialect at that. As a result, it is a bit difficult to integrate into other projects (praised be f2c), and the programming interface is simply horrible; worse, there are some Fortran-induced limitations such as a maximum of 20 species in a mixture. I was wondering whether it would be legal to buy a copy of such a database (they usually sell with source code, no one can read Fortran anyway); take the data, possibly reformatting it as XML; implement a new programming interface from scratch; and publish the package as free software. Thermodynamic data is not an intellectual creation but a mere measurement, which was most likely done not by the programmers but by scientists funded with our tax money. What are your experiences and opinions on the matter? For the record, I am based in Germany, so the EU database directive applies."
I can't find my copy of Supertrapp at the moment, but as I recall there is some strange wording in the license. It's definitely NOT public domain as asserted by the uninformed.
It's also not tabulated data. It's a collection of equations and empirical constants embedded in what may be the worst code I've ever seen.
It may be easier to track down the original papers and work from those, though that too is difficult as lots of the original work was published in obscure journals.
FWIW I am very comfortable w/ FORTRAN and prefer it for serious numerical work (default choice is C). I'm also quite skilled at interfacing FORTRAN to other languages.
I'm interested in working on such a project and have quite a bit of experience w/ the problem, though only limited experience w/ Supertrapp because it is so bad I tended to avoid using it unless I absolutely had to. Please send me an email so we can discuss more. rhb acm.org
Reg Beardsley
I do not know about this exact database, but many scientific databases are hand-curated and extensively reviewed. Many do not include every measurement published in the literature, but carefully and judiciously select those data points deemed, by expert opinion, most reliable. Thermodynamic databases do not contains "facts" per se, but measured data points which may or may not be close to the facts. The editing and review process, which is quite an investment, does often create a solid foundation for copyright. These databases are not just a routine business, like a reformatted dump of the data from a telephone company.