/var/lib/material-modelling/.config/matplotlib is not a writable directory
Matplotlib created a temporary cache directory at /tmp/matplotlib-y3cy5fvc because there was an issue with the default path (/var/lib/material-modelling/.config/matplotlib); it is highly recommended to set the MPLCONFIGDIR environment variable to a writable directory, in particular to speed up the import of Matplotlib and to better support multiprocessing.
/usr/lib/python3/dist-packages/ase/io/cif.py:408: UserWarning: crystal system 'cubic' is not interpreted for space group Spacegroup(221, setting=1). This may result in wrong setting!
  warnings.warn(
INFO: Reading configuration file /var/lib/material-modelling/data/LaB6.cif-QuantumEspresso-farhi-20261030-164404/config.toml.
INFO: Using material-modelling 26.10.30
INFO: Creating lattice/cell object from /var/lib/material-modelling/data/LaB6.cif-QuantumEspresso-farhi-20261030-164404/LaB6.cif [Fri Oct 30 16:44:08 2026]
INFO: supercell   = [2 2 2]
INFO: kpoints     = [3 3 3]
INFO: kpts_density= 1512
INFO: directory   = /var/lib/material-modelling/data/LaB6.cif-QuantumEspresso-farhi-20261030-164404
INFO: B6La Bravais lattice: CUB(a=4.157); Spacegroup: P m -3 m (221)
INFO: Estimated ~1345 G-vectors at ecut=408.2 eV (V=484.8 bohr^3). Max 13 MPI procs for >= 100 G-vectors/proc.
INFO: Limiting MPI from 128 to 13 processes (>=100 G-vectors/proc)
INFO: ecut        = 30.0 Ry (408.2 eV)
INFO: Using 12 MPI ranks (3 pools of 4) instead of 13.
INFO: Starting computations in file:///var/lib/material-modelling/data/LaB6.cif-QuantumEspresso-farhi-20261030-164404 [Fri Oct 30 16:44:08 2026]
INFO: Using calculator ESPRESSO.
INFO: Using kpoint [11 11 11]
INFO: Using kpoint [21 21 21]
INFO: Computing ground state [Fri Oct 30 16:44:09 2026]
INFO: Using 12 MPI ranks (3 pools of 4) instead of 13.
INFO: Computing electronic density of states [Fri Oct 30 17:49:09 2026]
Traceback (most recent call last):
  File "/usr/bin/material-modelling", line 2613, in compute_electronic_band_structure
    atoms.get_potential_energy()      # triggers calculation along BS
    ~~~~~~~~~~~~~~~~~~~~~~~~~~^^
  File "/usr/lib/python3/dist-packages/ase/atoms.py", line 770, in get_potential_energy
    energy = self._calc.get_potential_energy(self)
  File "/usr/lib/python3/dist-packages/ase/calculators/abc.py", line 24, in get_potential_energy
    return self.get_property(name, atoms)
           ~~~~~~~~~~~~~~~~~^^^^^^^^^^^^^
  File "/usr/lib/python3/dist-packages/ase/calculators/calculator.py", line 538, in get_property
    self.calculate(atoms, [name], system_changes)
    ~~~~~~~~~~~~~~^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/usr/lib/python3/dist-packages/ase/calculators/genericfileio.py", line 333, in calculate
    self.template.execute(self.directory, self.profile)
    ~~~~~~~~~~~~~~~~~~~~~^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/usr/lib/python3/dist-packages/ase/calculators/espresso.py", line 87, in execute
    profile.run(directory, self.inputname, self.outputname,
    ~~~~~~~~~~~^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
                errorfile=self.errorname)
                ^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/usr/lib/python3/dist-packages/ase/calculators/genericfileio.py", line 101, in run
    check_call(
    ~~~~~~~~~~^
        argv_command,
        ^^^^^^^^^^^^^
    ...<3 lines>...
        env=os.environ,
        ^^^^^^^^^^^^^^^
    )
    ^
  File "/usr/lib/python3.13/subprocess.py", line 419, in check_call
    raise CalledProcessError(retcode, cmd)
subprocess.CalledProcessError: Command '['/usr/bin/mpirun', '-np', '12', '/usr/bin/pw.x', '-npool', '3', '-in', 'espresso.pwi']' returned non-zero exit status 143.
INFO: Computing electronic band structure 1d [Fri Oct 30 17:49:10 2026]
INFO: Using 12 MPI ranks (3 pools of 4) instead of 13.
WARNING: Failed computing the 1d electronic band structure along BZ path. Ignoring.