. At one time, this space group was the most commonly found space group in small molecule crystals. In recent years, with the development of stronger structure solution algorithms, structures in other space groups have become more common.
Space Groups and the International Tables
Now we're ready to assemble the various symmetry operations and lattices into the space groups. There are a total of 230 three-dimensional space groups. They were worked out by three different investigators in the late 1800s, before the discovery of X-ray diffraction from crystals. The International Tables contain summary information for each of them and what we'll do now is look at the entries in the International Tables and go over the various symbols, etc for a few space groups. The one we'll start with is a centrosymmetric monoclinic space group,
. At one time, this space group was the most commonly found space group in small molecule crystals. In recent years, with the development of stronger structure solution algorithms, structures in other space groups have become more common.
In the Tables, there are 2 triclinic space groups, 13 monoclinic, 59 orthorhombic, 25 trigonal, 68 tetragonal, 27 hexagonal, and 36 cubic.
Here's an example of the type of space group entry you'd find in the older red versions of the International Tables. We'll go over it because these tables are still found in most labs. Later we'll look at the entry for this space group in the newer blue Tables.
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copyright © Ron Stenkamp stenkamp@u.washington.edu Most recent update 5/1/03