X-ray Statistics for Detailed Structural Model

From WikidChem

X-ray_statistics_for_detailed_structural_model Is the Structural Model realistic in Geometric Detail? In order to answer this question, we can go to experimental data gained by the ever-growing field of x-ray diffraction.

Since 1972, the database of molecules whose structures have been studied by x-ray crystallography has grown exponentially. By 2010, there will probably be over half a million molecules. The size and complexity of these molecules has also grown through the years.

With over 35 million bond lengths known, statistical studies can help predict how well our models reflect geometric realities.

In 1987 a study showed that in order to deal with bonds with reasonably reproducible distances it was necessary to define 119 different types of C-O bonds alone. There were 97 types of C-N bonds and 175 types of C-C bonds.

Because there are so many variations between bonds, molecular models must also incorporate thousands of constants into their calculations. -ST

last modified by J Michael McBride (mcbride) on Dec 14, 2006 12:53:59 AM