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I am looking for an computer parsable (CSV, XML, JSON, since I didn't find anything, I am happy with almost everything) file (or collection of files) that contains the information you can find in a simple table of nuclides. There are several more or less usable "browsers" and of course Wikipedia's tables, but none of them is quite what I want.

What I'd like to have is a list as simple as:

numer of protons, number of neutrons, half life, decay mode(s)

for each known isotope. But any other format that is parsable with reasonable effort to extract this data from a bigger set is also very welcome.

I have already found this, wich contains in a self-extracting .exe file (as a Linux user, I was happy to find out that 7zip can extract it just fine) one file for each element, and each file contains more than enough data: on the page there is also an 100-something pages long manual for the data format. I don't want to read this, so if anyone knows of a better (according to my needs) source, that'd be great!

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By googling, I found this little project:, which seems to include a list similar to what you describe (nuclear-wallet-cards.txt.gz). The fields are not explained but their meaning seem rather intuitive. The list seem to come from this place: where it is only available as a pdf. Perhaps the pdf can help explain any ambiguities. – jkej Jun 4 '14 at 21:36
This looks beyond awesome! I'm also going to code something in python, so I can perhaps use more of this than just the plain data. Out of curiosity, what did you search for? – Jasper Jun 4 '14 at 21:48
I'm glad you found it useful. I think my search terms were simply: text file list of nuclides – jkej Jun 5 '14 at 1:05

The canonical sources for this sort of information are the Nuclear Wallet Cards, for ground states and long-lived isomers, and the Evaluated Nuclear Structure Data File for all excited states and internal transitions. Both are actively maintained by the National Nuclear Data Center at Brookhaven National Lab.

The Nuclear Wallet Cards are available for free on paper by request, which is not what your question was, but they're so useful that I mention it whenever the opportunity arises.

The data used to generate the Nuclear Wallet Cards booklet is also available as an ASCII file by request. My impression is that the raw data files are more frequently updated, and so there aren't static links to them, but I could be mistaken.

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I'll definitely request this ASCII-file and see how useful this is. – Jasper Jun 5 '14 at 8:52
@Jasper It is probably the same data that jkej found, judging by the filename, except perhaps updated more recently. – rob Jun 5 '14 at 12:38
I just got a reply, the file is (up to minor updates) the same as in this comment… – Jasper Jun 6 '14 at 14:57

If you have access to Wolfram Mathematica (big if, I know), then you can use its IsotopeData function to programatically access these data. If you don't use it but you know someone who does, then it is easy to use that interface to build a file that you can then use with other tools.

This database is curated by Wolfram from a variety of sources, which include the Nuclear Wallet Cards among others.

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