                S.H.O.R.T  I.N.T.R.O  T.O  P.L.U.T.O.N
                ======================================
PLUTON is a program for interactive molecular graphics. It is designed
for use in a crystallographic context. However, it can be used for the
display and analyses of molecules in an orthogonal (Angstrom) coordinate
system as well. Various hardware/software/graphics platforms are supported.
The programs may be used free of charge in non-profit organisations.
     ** There is a charge of US $ 1000 for commercial users. **

(Note: Be aware of the fact that a growing number of journals (in 
  **   particular the ACS and Acta Cryst periodicals) require
  **   ORTEP-type of publication drawings. The companion program 
  **   PLATON may be used - among other applications - for that purpose)

Method of use:

1 - Pertinent data are given on/ read from a file (normally prepared
    either with an editor or by another program. The data may be in 
    several formats including those of the supplied testdata files.
    Formats that should work are: CIF, shelxl.res, PDB, Cart3d, Fdat.
    The name of the file is not essential i.e. no information on the
    file contents is taken from its name. The data type is guessed 
    from the file contents.

2 - The program is started with the command line 'pluton cyto.spf'
    with the data-file as argument.

3 - The program prompts the user for instructions (A build-in help
    function lists all available instructions). Most instructions 
    are defaulted. A PLUTON session consists of a cyclic process of
    content/style/viewpoint type of modification instructions and
    a PLOT instruction to inspect the result of the current settings.

4 - As an example, try the following simple sequence of instructions
    with the 'cyto.spf' file. (Note: Instructions given in upper-case
    here, however lower case is also acceptable)

    a) PLOT        This will give a default stick style plot. The plot 
                   style may be changed into the 'straw-mode' with the
                   instruction

    b) STRAW       (Note: Keyboard control is retained after hitting the
                          Return key)

                   followed by:

    c) PLOT        to inspect the result.

    d) XROT 45     followed by

    e) PLOT        will result in a molecule rotated by 45 degrees 
                   over the horizontal X-axis.

    f) CPK GLOBE   will change again the plot style into a space filling
                   model followed by 
    g) PLOT

    h) SET META PS and   (Note: Postscript is default on UNIX versions)

    i) SET META ON and

    j) PLOT        will generate a disk-file that can be send to a
                   PostScript laserprinter (Other options are described
                   in the HELP GRAPHICS option

    k) END         finishes the session

=======
= Note: Make sure that the input (= instruction) window does not overlap
======= the graphics window. This applies to SGI-systems in particular
        that donot provide automatic 'save-under'. 

                          ***********
                          N.O.T.I.C.E
                          ***********

As of 1-1-97 PLUTON is part of the program PLATON. See PLATON-README.
All future development of PLUTON will be available in PLATON only.

                            =====================

Dr. A.L. Spek
Lab. for Kristal- and Structural Chemistry
Byvoet Center for Biomolecular Research
University of Utrecht
Padualaan 8
3584 CH Utrecht
The Netherlands

spea@xray.chem.ruu.nl
