Novel layered lithium nitridonickelates; effect of Li vacancy concentration on N co-ordination geometry and Ni oxidation state

(Note: The full text of this document is currently only available in the PDF Version )

Marten G. Barker, Alexander J. Blake, Duncan H. Gregory, Daniel J. Siddons, Susan E. Smith, Peter P. Edwards and Thomas A. Hamor


Abstract

New compounds in which nickel is substituted for lithium in lithium nitride show evidence of high lithium vacancy concentrations and an ordering of these vacancies to form new structural variants.


References

  1. See, for example: D. H. Gregory, J. Chem. Soc., Dalton Trans., 1999, 259 Search PubMed; R. Niewa and F. J. DiSalvo, Chem. Mater., 1998, 10, 2733 RSC.
  2. See, for example: R. Juza and F. Hund, Z. Anorg. Allg. Chem., 1948, 257, 1 Search PubMed; R. Juza, H. H. Weber and E. Meyer-Simon, Z. Anorg. Allg. Chem., 1953, 273, 48 CAS.
  3. W. Sachsze and R. Juza, Z. Anorg. Allg. Chem., 1949, 259, 278 CAS.
  4. R. Juza, K. Langer and K. von Benda, Angew. Chem., 1968, 80, 373; Angew. Chem., Int. Ed. Engl., 1968, 7, 360 Search PubMed.
  5. U. V. Alpen, J. Solid State Chem., 1979, 29, 379 CrossRef.
  6. Cleaned, pure lithium was added to an excess of molten sodium contained in a stainless-steel crucible at 250 °C. The cooled crucible was sealed inside a stainless-steel distillation vessel which was evacuated and filled with nitrogen gas (ca. 2 atm). The vessel was heated to 650 °C with the nitrogen pressure monitored using a pressure transducer. Excess Na was removed by vacuum distillation at 350 °C for 12 h.
  7. Crystal data: Li5Ni3N3, M= 252.9, hexagonal space group P[6 with combining macron]2m(no. 189), a= 6.475(3), c= 3.555(2)Å, Z= 1, V= 129.1(3)Å3, Dc= 3.253 g cm–3, µ= 10.67 mm–1. 868 reflections measured at 293(2) K, 109 independent (Rint= 0.0712). Data collected on a Rigaku R-Axis II area detector diffractometer with graphite monochromated Mo-Kα radiation (λ= 0.71073 Å). The structure was solved by direct methods with SHELXS-86a, and refined by least squares within SHELXL-93.bw= 1/[σ2(Fo2)+(0.040P)2+ 0.59P] where P=(Fo2+ 2Fc2)/3 R1 = 0.0351, wR2 = 0.0884; LiNiN, M= 79.66, hexagonal space group P[6 with combining macron]m2 (no.187), a= 3.758(1), c= 3.540(1)Å, Z= 1, V= 43.30(2)Å3, Dc= 3.055 g cm–3. µ= 10.606 mm–1, 1440 reflections measured at 297(2) K, 171 independent (Rint= 0.024). Data collected on a Stadi-4 diffractometer with Mo-Kα radiation (λ= 0.71073 Å). The structure was solved by direct methods with SHELXL-86a and refined by least squares within SHELXL-93.bw= 1/[σ2(Fo2)+(0.0584 P)2] where P=(Fo2+ 2Fc2)/3. R1 = 0.0374, wR2 = 0.0803. (a)G. M. Sheldrick, Acta Crystallogr., Sect. A, 1990, 46, 467; (b)G. M. Sheldrick, SHELXL-93, Program for Crystal Structure Refinement, University of Gottingen, Gottingen, Germany, 1993 Search PubMed; CCDC 182/1262. See http://www.rsc.org/suppdata/cc/1999/1187/ for crystallographic files in .cif.format.
  8. The alternative disordered model was refined in space group P6/mmm with an R1 factor higher by 0.01 (0.046). The key differences compared to the P[6 with combining macron]m2 model are the partial occupancy of the interplane site by Li (Li:Ni = 0.23:0.87) and disordered Li vacancies in the Li-N planes giving a Li(2) site partial occupancy (0.55).
  9. W. H. Baur, Crystallogr. Rev., 1987, 1, 59 Search PubMed.
  10. H. J. Beister, S. Haag, R. Kniep, K. Strössner and K. Syassen, Angew. Chem., 1988, 100, 1116 CAS; Angew. Chem., Int. Ed. Engl., 1988, 27, 1101 Search PubMed.
  11. A. Rabenau and H. Schultz, J. Less-Common Met., 1976, 50, 155 Search PubMed.
  12. M. Y. Chern and F. J. DiSalvo, J. Solid State Chem., 1990, 88, 459 CAS.
  13. T. Yamamoto, S. Kikkawa and F. Kanamaru, J. Solid State Chem., 1995, 115, 353 CrossRef CAS.
  14. J. Klatyk, P. Hohn and R. Kniep, Z. Kristallogr., 1998, 213, 31 CAS.
  15. N. E. Brese and M. O'Keeffe, Acta Crystallogr., Sect. B, 1991, 47, 192 CrossRef.
  16. M. T. Weller, S. E. Dann, P. F. Henry and D. B. Currie, J. Mater. Chem., 1999, 9, 283 RSC.
  17. N. A. Martem'yanov, V. Kh. Tamm, V. P. Obrosov and Z. S. Martem'yanova, Inorg. Mater., 1995, 31, 65 Search PubMed.
Click here to see how this site uses Cookies. View our privacy policy here.