Bugs fixed¶
PDB with a box of size 1 Angstrom are interpreted as having no PBC¶
PDB files with structures not determined from X-ray should have a unit-cell with P=1 and dimensions of 1 Angstrom to indicate no periodic boundary conditions. GROMACS now interprets such structures as not having PBC.
PDB trajectory output now writes correct per-frame PBC type¶
When writing PDB trajectories, the PBC type of the system was ignored
and instead guessed from the box. As a result, the CRYST1 record
was written incorrectly for screw PBC (wrong space group and cell length).
Analysis tools now always process time values in double precision¶
This avoids picking incorrect frames when times values are large.
Request the MPI thread support required by CP2K¶
With external MPI, setting the new environment variable
GMX_USE_MPI_THREAD_MULTIPLE to any value requests MPI_THREAD_MULTIPLE.
The default MPI initialization is unchanged. QM/MM setup checks the linked
CP2K version and reports a helpful fatal error if it requires
MPI_THREAD_MULTIPLE but MPI was initialized with insufficient thread support.
This applies to CP2K 2027 or later, CP2K 2026.2 development builds, and
unrecognized CP2K versions. Users are instructed to set the environment
variable before launching GROMACS.