DIRDIF - ORBASE, ORUSER files

The ORBASE, ORUSER database of common fragments

ORBASE is a database containing molecular fragments to be used as input models in the program ORIENT = Patterson -vector-search-rotation functions. Each entry consists of a set of atomic parameters, which define the positions of the atoms relative to an internal origin.

The structure of the data base is kept simple: it is too small for sophisticated retrieval and editing procedures, but the user can easily add fragments from the literature and from his own work, which are of relevance to his structural research. This can be done in this file as well as in the user-oriented file ORUSER.

Before searching the ORBASE file, DIRDIF will scan through ORUSER.

An entry (one model = one molecular fragment) is identified by a number. Some entries also have a name. Technical details and some illustrative examples are given in the top lines of the distributed file ORBASE.