X-ray Diffraction: General Purpose

Three X-ray diffraction (XRD) systems are available for analysis of crystalline materials:

1. General purpose XRD system for phase analysis of polycrystalline samples
2. Special applications XRD system with high- and low-temperature sample stages, plus focusing and parallel beam optics
3. Four-circle XRD system with high-resolution optics (HRXRD, Double Crystal, or Triple-Axis geometry) for studying large-face single crystals and epitaxial thin films.

System Configurations and Operational Overview

All work with the following systems and in EMSL labs must be performed in compliance with EMSL practices and permits.

The general purpose X-ray diffractometer is a Philips X'Pert MPD system with a vertical Θ-Θ goniometer (190 mm radius). The X-ray source is a long-fine-focus, ceramic X-ray tube with Cu anode. Normal operating power is 40 kV, 50 mA (2.0 kW). The system optics consist of programmable divergence, anti-scatter, and receiving slits, incident and diffracted beam soller slits, a curved graphite diffracted beam monochromator, and a proportional counter detector (Bragg-Brentano parafocusing geometry). The principal application of this system is phase analysis of polycrystalline samples. The Multi-Purpose Sample Stage supports typical cavity-type powder mounts and will also accommodate monolithic specimens of a wide variety of sizes and shapes.

Analysis Software

The principal XRD data analysis program is JADE (Materials Data Inc., Livermore, CA.). JADE supports comprehensive analysis of XRD patterns, including phase identification, peak profile fitting, indexing, unit cell refinement, Rietveld analysis, etc. Available software for thin film applications includes the Bede programs RADS and REFS, plus the Philips programs X'Pert Texture, X'Pert Epitaxy, and WINGIXA.

Reference Database

The principal reference database is the Powder Diffraction File (International Centre for Diffraction Data, Newtown Square, PA.).

All Related Publications Related Publications

1. Advancements Toward the Greener Processing of Engineered Nanomaterials -- Effect of Core Size on the Dispersibility and Transport of Gold Nanocrystals in Near-Critical Solvents.
2. Antibody recognition force microscopy shows that outer membrane cytochromes OmcA and MtrC are expressed on the exterior surface of Shewanella oneidensis MR-1.
3. Suppression of conductivity in Mn-Doped ZnO Thin Films.
4. Simultaneous MS-IR Studies of Surface Formate Reactivity Under Methanol Synthesis Conditions on Cu/SiO2.
5. Effect of the Ligand Shell Composition on the Dispersibility and Transport of Gold Nanocrystals in Near Critical Solvents.