Crystallography & NMR System


Provides a hierarchical approach for the most commonly used algorithms in structure determination.


Crystallography & NMR System (CNS) is the result of an international collaborative effort among several research groups. The program has been designed to provide a flexible multi-level hierarchical approach for the most commonly used algorithms in macromolecular structure determination. Highlights include heavy atom searching, experimental phasing (including MAD and MIR), density modification, crystallographic refinement with maximum likelihood targets, and NMR structure calculation using NOEs, J-coupling, chemical shift, and dipolar coupling data.



NMRbox Version Software Version
3.0.0 1.21, 1.3,
1.0.0 1.3,
2.0.0 1.3,


  • Structure Determination
  • Structure Refinement


Crystallography \& NMR system: A new software suite for macromolecular structure determination
Brünger Axel T, Adams Paul D, Clore G Marius, DeLano Warren L, Gros Piet, Grosse-Kunstleve Ralf W, Jiang Jian-Sheng, Kuszewski John, Nilges Michael, Pannu Navraj S,
Acta Crystallogr D Biol Crystallogr. 1998; 54(5): 905--921