Neutrons in chemistry : contributions of single crystal neutron diffraction to coordination chemistry

1. Introduction Single crystal neutron diffraction is the technique of choice for unambiguously and accurately locating hydrogen atoms even in the presence of nearby “heavy atoms”. Recent advances in instrumentation and neutron sources are opening up new possibilities: in particular the use of fairly small crystals and short data collection times. 2. Results and Discussion We will report three examples to illustrate the power of this technique in inorganic chemistry: 1) the first unambiguous structural evidence for non-conventional hydrogen bonding between a water molecule and a metal center in trans-[PtCl2(NH3)(N-glycine)]∙H2O.[1] 2) The coordination geometries of the binary platinum hydrides [Pt2(P-P)2(H)3]+ (P-P = dppb: 1,4–Bis(diphenylphosphino)butane and dpe: 1,2–Bis(diphenylphosphino)ethane). 3) The unambiguous location of deuterium atoms in the deuterated form of RuH2(η2-H2)2(PCyp3)2 (Cyp = cyclopentyl) complex as a proof of the metal-mediated C-H activation.[2] 3. References [1] Silvia Rizzato, Jacqueline Bergès, Sax A. Mason, Alberto Albinati and Jiří Kozelka, Angew. Chem. Int. Ed., in press. [2] M. Grellier, L. Vendier, B. Chaudret, A. Albinati, S. Rizzato, S. A. Mason and S. Sabo-Etienne J. Am. Chem. Soc., 2005,127 (50), 17593.