The structure of formamide oxime in the crystal phase (P2 1 2 1 2 1 ) was completely optimised with standard gradient procedures using a 15-molecule cluster surrounded by point charges. The calculations were performed using 4-21G and 6-31G basis sets and in the SCF step of the calculations the MIA approach was used. Results are in better agreement with experimental results than a previous study, in which only point charges were used to model the crystal.