Common mistakes

• Write the energy per atom (or per unit cell of the lattice) in the */energy files. One should write the energy per unit cell of the structure (that is, in the way a first-principles code usually gives it).
• Errors in the lat.in file. Use the corrdump -sym ; more sym.out command to analyse the symmetry of the lattice and see if it correspond to your expectations. You can also use corrdump -2=10 -clus ; more clusters.out to verify the symmetrically distrinct pairs are what you expect them to be.

• When the structures are not generated by MAPS (i.e. you typed them it), beware of typos. MAPS will detect if a structure is incompatible with the lattice but it will not detect another very common mistake: putting the energy and str.out files that correspond to different structures in the same directory. To check for this error, look at the residual plot generated by mapsrep.

• When copying the lat.in files provided as examples, make sure you make all the required changes. (i) Change the atom names. (ii) Set the lattice parameters (first 3 numbers in the file) to values that are at least as large as the true lattice parameter (otherwise, first-principles code can be unable to properly relax the geometry of the structure is the atoms are too close to one another initially).