Structural and compositional tuning of layered subnitrides; new complex nitride halides.
New quaternary bimetallic nitride halides and the first examples of quintinary nitride mixed halides have been synthesised in the phase system Ca - Sr - N - Cl - Br. The variation in structure with composition has been investigated by powder X-ray and powder neutron diffraction techniques. All compounds crystallise in the R-3m spacegroup, with the anti-alpha-NaFeO(2) structure. The layered compounds exhibit unprecedented coexistent disorder of both cations and anions in which only nitride solely occupies a discrete crystallographic position. [N(Ca,Sr)(2)](+) layers alternate with halide ions (Cl, Br)(-), which fill the octahedral voids between the positively charged sheets. A dual cationic-anionic substitution approach allows all aspects of the anisotropic structure to be controlled, including the thickness of the ionic layers and the [N(Ca,Sr)(2)](+) interlayer spacing.
School of Chemistry, University of Nottingham, Nottingham, United Kingdom NG7 2RD.
Michael A
MA
Brogan
Robert W
RW
Hughes
Ronald I
RI
Smith
Duncan H
DH
Gregory
D006219:Halogens / Q000737:chemistry*; D008958:Models, Molecular; D015394:Molecular Structure; D017672:Nitrogen Compounds / Q000737:chemistry*; D009942:Organometallic Compounds / Q000138:chemical synthesis / Q000737:chemistry*
D006219:Halogens; D017672:Nitrogen Compounds; D009942:Organometallic Compounds