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lmmentel / mendeleev

A python package for accessing various properties of elements, ions and isotopes in the periodic table of elements.
https://mendeleev.readthedocs.io
MIT License
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g factor data missing? #97

Open jkshenton opened 1 year ago

jkshenton commented 1 year ago

Hi!

I'm not sure this is a bug, but I don't seem to find a lot of the g-factor data/nuclear magnetic dipole moments for various isotopes. For e.g. for 51V, a nuclear magnetic dipole moment of +5.1464(7) nm is given, but I can't seem to find this in mendeleev. Could it be to do with with the way the CSV files are parsed? Or am I missing something?

Thanks!

lmmentel commented 1 year ago

I can see that the db has the correct value of spin and quadrupole moment for 51V but for some reason the g-factor is missing. I think there is a bit of discrepancy between the files since the paper reports the value you mention

23 V 51 0 stable 7/2- +5.1464(7) N 1981Ha26/1951Pr02 ZP A300 111 (81)/PR 81 20 (51)

but I cannot find this value in the csv file that reports only the value for spin 5/2.

I'm not sure yet how to validate the current data consistency and fix the issue. Any ideas?

If you found any other isotopes for which there are missing or wrong values please let me know.

jkshenton commented 1 year ago

Thanks for the quick response!

I'm not sure why the value isn't in the 'recommended' csv file that you linked to, but it does seem to be in this one: https://www-nds.iaea.org/nuclearmoments/nuc_mom_compilation.csv

It think there are a bunch of others:

I can make a full list, but maybe that's enough to find a pattern?

Thanks, Kane

PS The same ones are missing in the IsotopeTable.jl package, it seems.

lmmentel commented 1 year ago

The missing values are indeed in the compilation csv but the challenge there is that there are multiple values reported per isotope and some data is missing (spins for some rows). What add to the inconvenience is that the column with magn dipole values sometimes has numbers and for other rows it has reference keys (I guess). I'm not quite sure how to interpret that.

jkshenton commented 1 year ago

Hmmm yes that's tricky... There is this pdf with a seemingly complete, corrected set of recommended values for the nuclear magnetic dipole moments:

https://www-nds.iaea.org/publications/indc/indc-nds-0794.pdf

(see Appendix 1)

but I can't see a corresponding .csv file unfortunately...

lmmentel commented 5 months ago

@jkshenton have you managed to solve it or find a workaround?