Could not find nuclide U235

I’m sure we can get either the official or this downloader working for you. Are you able to attend the monthly drop is session today, we can do a screen share and get things working?

I would be tempted to move uranium and iron to the element section

So you have

‘’’
openmc_data_downloader -l TENDL-2019 -e U Li Na Si Fe
‘’’

Then export the environmental variable.

‘’’
export OPENMC_CROSS_SECTIONS=home/dalia/cross_sections.xml
‘’’