TITAN: A MOLECULAR GRAPHICS PROGRAM TO AID STRUCTURE SOLUTION AND REFINEMENT WITH THE SHELX SUITE OF PROGRAMS. Jim Simpson and Keith A. Hunter, Department of Chemistry, University of Otago, P.O. Box 56, Dunedin, NEW ZEALAND

TITAN is a Windows based molecular graphics program designed to be used exclusively in conjunction with SHELXS-86¹ for structure solution and SHELXL-93² and/or SHELX-76³ for structure refinement. The program facilitates the on-screen assignment of peaks from the direct methods E-map or Patterson map to individual atom designations. Once these designations are completed, a file is written that can be input directly to the SHELXL-93 refinement program without modification. TITAN can also be used in the location of additional atoms in series of least-squares and difference Fourier cycles and as an aid to the inclusion of hydrogen atoms into the refinement using the HFIX and/or AFIX commands.

TITAN runs in the Windows environment and requires a 386 or better processor with a minimum of 4Mb memory. Hard-copy plots can be obtained using any Windows compatible printer. In addition, TITAN will generate output files that can be processed using the public-domain ray tracing software Persistence of Vision (POVRay) to produce exceptionally high quality 24-bit colour images for reproduction.

A demonstration of the operation of the TITAN program will be given as part of this poster presentation.

1 Sheldrick, G.M. (1986) SHELXS-86 A program for the solution of crystal structures from diffraction data. University of Gttingen, Federal Republic of Germany

2 Sheldrick, G.M. (1995) SHELXL-93 J. Appl. Cryst. in preparation

3. Sheldrick, G.M. (1976) SHELX-76 Program for crystal structure determination, University of Cambridge, England