How was Herbert A. Hauptman awarded the Nobel Prize?

Name: Herbert A. Hauptman. 
Country: New York City.
Date of Birth: 14 February 1917.
Date of Death: 23 October 2011.
The subject of Study: X-ray diffraction equation molecule.
Noble Prize Year: Nobel Prize for Chemistry in 1985 for their research developed mathematical methods for deducing the molecular structure of chemical compounds from the patterns formed when X-rays are diffracted by their crystals.