Problem on the openmc.run() ,cross sections file

User Support
1

hi ,I’m a new in openMC,i have a problem on the openmc.run?
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             | The OpenMC Monte Carlo Code
   Copyright | 2011-2024 MIT, UChicago Argonne LLC, and contributors
     License | https://docs.openmc.org/en/latest/license.html
     Version | 0.15.0
    Git SHA1 | 84fb85977f46e162fea8f5a20ea653a3ec62ac24
   Date/Time | 2025-02-17 22:37:48

MPI Processes | 1
OpenMP Threads | 4

Reading settings XML file…
ERROR: No cross_sections.xml file was specified in materials.xml or in the
OPENMC_CROSS_SECTIONS environment variable. OpenMC needs such a file to
identify where to find data libraries. Please consult the user’s guide
at https://docs.openmc.org/ for information on how to set up data
libraries.

MPI_ABORT was invoked on rank 0 in communicator MPI_COMM_WORLD
Proc: [[4301,0],0]
Errorcode: -1

NOTE: invoking MPI_ABORT causes Open MPI to kill all MPI processes.
You may or may not see output from other processes, depending on
exactly when Open MPI kills them.

RuntimeError Traceback (most recent call last)
Cell In[105], line 1
----> 1 openmc.run()

File ~/miniforge3/envs/openmc-env/lib/python3.12/site-packages/openmc/executor.py:314, in run(particles, threads, geometry_debug, restart_file, tracks, output, cwd, openmc_exec, mpi_args, event_based, path_input)
261 “”“Run an OpenMC simulation.
262
263 Parameters
(…)
305
306 “””
308 args = _process_CLI_arguments(
309 volume=False, geometry_debug=geometry_debug, particles=particles,
310 restart_file=restart_file, threads=threads, tracks=tracks,
311 event_based=event_based, openmc_exec=openmc_exec, mpi_args=mpi_args,
312 path_input=path_input)
→ 314 _run(args, output, cwd)

File ~/miniforge3/envs/openmc-env/lib/python3.12/site-packages/openmc/executor.py:125, in _run(args, output, cwd)
122 error_msg = ‘OpenMC aborted unexpectedly.’
123 error_msg = ’ '.join(error_msg.split())
→ 125 raise RuntimeError(error_msg)

RuntimeError: No cross_sections.xml file was specified in materials.xml or in the OPENMC_CROSS_SECTIONS environment variable. OpenMC needs such a file to identify where to find data libraries. Please consult the user’s guide at https://docs.openmc.org/ for information on how to set up data libraries. -------------------------------------------------------------------------- MPI_ABORT was invoked on rank 0 in communicator MPI_COMM_WORLD Proc: [[4301,0],0] Errorcode: -1 NOTE: invoking MPI_ABORT causes Open MPI to kill all MPI processes. You may or may not see output from other processes, depending on exactly when Open MPI kills them. --------------------------------------------------------------------------

2

Hi there. It seems that you have not set up your cross sections yet. Follow the instructions in the documentation:
https://docs.openmc.org/en/v0.12.1/usersguide/cross_sections.html
The easiest way to go about it is to use the pre-generated HDF5 libraries from Data Libraries | OpenMC and then assign an environment variable to the cross_sections.xml file inside the library.

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