The first step in the program is the input of the structure's data. The data can be given using the form or it can be loaded from a file. If you have been saved the structure's data into a file, follow the link at the top of the form to load it, otherwise fill the fields in the form at this page.

When the data for the structure is given filling a form fields, they start with the formulae of the compound, the number of its space group in the International Tables for Crystallography, Vol A, and the cell constants. Also, it is obligatory to give the number of the atoms in the asymmetric unit. This number will be used on the next step to provide a table for giving the atomic positions data with the correct number of rows.

If you want to give the structure data (cell constants and atomic positions) in a non conventional setting, than you must give the matrix that transforms the conventional setting to that non conventional one. Otherwise, just leave the unit matrix.

When you have filled all of the data, click on the [Submit] button to go to the next step where you should give the data for the atoms in the asymmetric unit.