"All we have discovered is that it starts with a single individual - always a child - and then spreads explosively, like the formation of crystals round the first nucleus in a saturated solution." Arthur C. Clarke (Childhood's End, 1953)


SHELX - Probably the most 'famous' structure solution/refinement program using both Patterson and direct methods. We own two windows licenses of the Shelxtl software package. We mainly use Xprep, XS, XL (or XH), XP ('old fashioned' but very useful to visualize Q peaks, a must have) and XCIF.
winGX - Structure solution / refinement / analyses.
Jana2006 - Structure Solution / refinement for commensurate / incommensurate structures.
Difdif (windows version here) - Structure solution by Patterson and direct methods. A very powerful program for structure solution. It works beautifully for crystal structures of coordination and organometallic compounds.
Sir2004 - Structure solution by Patterson and direct methods. Useful for weak data sets.
Platon (windows version here) - A multipurpose crystallographic tool. This is Ton Spek's program. PLATON is a versatile tool for multianalyses of crystal structures. Some of the nicest features in PLATON are SYSTEM-S (a guided route toward structure determination & refinement), ORTEP (displacement ellipsoid plots), CONTOUR-DF/-FO (contouring of difference Fourier/Fo maps), SQUEEZE (remove contribution of heavily disordered solvent molecules, structural voids), ADDSYM (check for additional/missing symmetry), TwinRotMat (check for unaccounted twinning) and VALIDATION/FCF-VALID (validation for cif/fcf files).
ORTEP 3 - A decent software to make displacement ellipsoid plots of good quality
CSD (Cambridge Structural Database) - This is the main database for crystals structures of organic, organometallic and coordination compounds.We have two licenses of the CSD. For each crystal mounted on our diffractometer, and for each successful unit-cell determination, we perform a quick search in the CSD in order to check for known compounds (starting materials, published structures, etc.). This practice requires very little time, and may turn out to be very useful.
Mercury - Crystal structure visualization and analysis. A very complete and intuitive software (free of charge) featuring crystal packing/hydrogen bonding analyses. Mercury allows to display bond distances, bond angles, torsion angles, short contacts, centroids, Miller planes (hkl) and more. Plots with a large variety of styles can be drawn at high resolution for publication purposes. Mercury has also a very user-friendly interface. Licensed Mercury version (installed along with the CSD) offers even more options (display voids, graph sets, overlay structures, etc.)
Encifer - A program for viewing, editing and visualising CIFs. Encifer is a well designed CIF editor, and is free of charge. Encifer indicates errors and give warnings for 'broken' cif files. Encifer allowd 3-D visualization as well.
PublCIF - A CIF editor for authors.

Other Links

ACS (American Chemical Society)

RSC (Royal Society of Chemistry)

CCDC (Cambridge Crystallographic Data Centre) - The CCDC is dedicated to the advancement of chemistry and crystallography for the public benefit through providing high-quality information services and software.

ISI Web of Knowledge

(IUCr) Core Dictionary

(IUCr) checkCIF - Essential to check the cif files. It is the online cif validation.

(IUCr) printCIF - Printcif allows to preview the approximate style in which cif files will be typeset. Probably not as useful as the previous link unless you want to publish in Acta C or Acta E.

Prepare experimental tables - A very nice link which prepares automatically experimental tables from the cif files. Very useful to append the crystallographic data within manuscripts.