Determination of the space group and unit cell for a periodic solid

We present the code for finding a space group and appropriate crystallograp hy unit cell for a periodic solid. A space group is found in a standard for m (as given in the International Tables for Crystallography (1992)). An arb itrary choice of the unit cell is allowed as an input in the sense that the re exists the infinity of geometrical choices. In addition, the sets of the symmetrically equivalent atoms and the point group for each set, shift vec tors which do not change the representation of the space group, are calcula ted. (C) 2001 Elsevier Science B.V. All rights reserved.