Bragg Institute

Analysis of neutron scattering data using modelling methods

In order to help users analyse their data more thoroughly we offer some modelling support. We are happy to get users started on modelling where this is appropriate using our cluster and software for which we have eneral licences: forcite, discover,Dmol3, CASTEP, GULP Our resources are limited so would expect users to continue using their own resources, unless there is a specific collaboration or joint project. In the case of collaboration other software is also available.

The main uses are:

  1. Verifying crystal structures again fist-principles energy calculations.
  2. Deriving and energetically reasonable starting models for structure refinement.
  3. Choosing between different disordered structures.
  4. Structure of glasses and amorphous systems.
  5. Spin-density distributions
  6. Electron density distribution
  7. Lattice dynamics for temperature factors and inelastic scattering
  8. Molecular dynamics for temperature factors, thermal expansion and inelastic scattering.
  9. Band structure and density of states
  10. Elastic, dielectric and piezoelectric constants
  11. Optical properties (UV spectra, polarizability, reflectivity and refractive index)

For the purpose of starting we mainly use modules within Materials Studio which provides a fairly simple interface to all of the above. We can point users to other more academic software that is readily available for use on university clusters of facilities such as APAC.

For further information contact either Don Kearley (gordon.kearley@ansto.gov.au ) of Max Avdeev (maxim.avdeev@ansto.gov.au) or your favourite local contact.

Publications so far involving use of these facilities are:

1. P.J. Saines, J.R. Spencer, B.J. Kennedy, M. Avdeev
"Structures and crystal chemistry of the double perovskites Ba2LnB′O6 (Ln=lanthanide B′=Nb5+ and Ta5+): Part I. Investigation of Ba2LnTaO6 using synchrotron X-ray and neutron powder diffraction"
Journal of Solid State Chemistry, Volume 180, Issue 11, Pages 2991-3000.

2. B. Rowda, M. Avdeev, P.L. Lee, et al.
"Structures of 6H perovskites Ba3CaSb2O9 and Ba3SrSb2O9 determined by synchrotron X-ray diffraction, neutron powder diffraction and ab initio calculations"
Acta Crystallographica Section B-Structural Science, Volume 64, pages 154-159.

3. N. Sharma, R.B. Macquart, M. Christensen, M. Avdeev, Y.S. Chen, C.D. Ling
"Structure and crystal chemistry of fluorite-related Bi38Mo7O78 from single crystal X-ray diffraction and ab initio calculations"
Journal of Solid State Chemistry Volume: 182, Issue: 6, Pages: 1312-1318 (2009)

4. S. Yakovlev, M. Avdeev; M. Mezouar
"High-pressure structural behaviour and equation of state of NaZnF3"
Journal of Solid State Chemistry Volume:182, Issue 6, Pages: 1545-1549 (2009)

5. L. Noren, R.L. Withers, D.J. Goossens, M.M. Elcombe, G.J. Kearley,
"Coupled Li1+/Nb5+ and O2-/F- ordering on the Na and Cl sites of the average NaCl-structure of Li4NbO4F"
Journal of Solid State Chemistry, 182(5), 1109-1114 (2009)

6. G.J.Thorogood, B.J. Kennedy, V.K. Peterson, M.M. Elcombe, G.J. Kearley, J.V. Hanna, V. Luca
"Anomalous Lattice Parameter Increase in Alkali Earth Aluminium Substituted Tungsten Defect Pyrochlores"
Journal of Solid State Chemistry 182, 457-464 (2009)

7. C. White, J. Provis, D. Riley, G.J. Kearley, J. Van Deventer
"What is the Structure of Kaolinite? Reconciling Theory and Experiment"
J. Phys. Chem B, 113(19), 6756-6765 (2009)

8. C.D. Ling, M. Avdeev, R. Kutteh et al.
"Structures, Phase Transitions,  Hydration and Ionic Conductivity of Ba4Nb209"
Chemistry of Materials, Volume: 21, Issue: 16, Pages: 3853-3864 (2009)

9. C.D. Ling, B. Rowda, M. Avdeev, et al
"Structures, phase transitions and microwave dielectric properties of the 6H perovskites Ba3BSb209, B = Mg, Ca, Sr, Ba
Journal of Solid State Chemistry, Volume: 182, Issue: 3 (2009)

10. E.A. Juarez-Arellano, A. Friedrich, D.J. Wilson, et al.
Single-crystal structures of HoBaCo407 at ambient conditions, at low temperature, and at high pressure
Physical Review B, Volume: 79, Issue: 6, Article Number: 064109 (2009)

11.F. Fontaine-Vive, F. Merzel, M.R. Johnson, G.J. Kearley
Collagen and component polypepties: Low frequency and amide vibrations
Chemical Physics 355 141-148 (2009)

12. L. van Eijck, A.S. Best, S. Long, F.Fernandez-Alonso, D. MacFarlane, M. Forsyth and G.J. Kearley
Localized Relaxational Dynamics of Succinonitrile
J. Phys. Chem. C, 113(33), 15007-15013 (2009)