Nanoscale-Ordered Materials Diffractometer

NOMAD |  BL-1B | SNS

NOMAD

Mission Statement

Study of a large variety of samples ranging from liquids, solutions, glasses, polymers, and nanocrystalline materials to long-range-ordered crystals.

Instrument Description

NOMAD is a high-flux, medium-resolution diffractometer that uses a large bandwidth of neutron energies and extensive detector coverage to carry out structural determinations of local order in crystalline and amorphous materials. It enables studies of a large variety of samples ranging from liquids, solutions, glasses, polymers, and nanocrystalline materials to long-range-ordered crystals. The enhanced neutron flux at SNS, coupled with the advanced neutron optics and detector features of NOMAD, allows for unprecedented access to high-resolution pair distribution functions, small-contrast isotope substitution experiments, small sample sizes, and parametric studies.

Applications

  • Environmental (e.g., solvent) effects on and direction of nanoscale structure formation
  • In situ structural changes in nanoscale oxide catalysts used in automobile catalytic converters
  • Structure of hydrogen storage materials under in situ conditions
  • Transient structures of materials under extreme conditions (e.g., at high temperature or high pressure under the influence of transient fields or in metastable states)

Specifications

Beam line 1B
Moderator decoupled poisoned supercritical hydrogen
Moderator-to-sample distance 19.5 m
Sample-to-detector distance 0.5 – 3 m
Wavelength range 0.1 – 3 Å
Momentum transfer range 0.04 – 100 Å-1
Detector angular range 3 – 175° scattering angle
Initial coverage 4.0 steradian
Full detector complement 8.2 steradian
Flux on sample ~1 × 108 neutrons cm-2 sec-1

Sample Environment

Automated Sample Changer with Cobra Cryostream 90-500K, vanadium sample cans, quartz capillaries, NMR & kapton tubes
Orange Cryostat 2-310K, vanadium sample cans
ILL furnace Room temperature -1200C, vanadium sample cans (Compatibility of sample with vanadium at high temperatures required)
Aerodynamic levitator 800-3000K, container-less solid samples
High Voltage Stick +-10kV at room temperature, no temperature control, ceramic solids
Gas Handling Panel 2-310K in Cryostat + gas handling, vanadium sample cans

More information can be found in this NOMAD overview presentation or "The Nanoscale Ordered Materials Diffractometer NOMAD at the Spallation Neutron Source SNS," published in Nucl. Inst. and Meth. B.