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XRD: other equipment

Contact: Chief Research X-Ray Lab Technician

Dr. Giulio I. Lampronti, JavaScript must be turned on for you to be able to see this address
Tel: 68333 

CURRENTLY INOPERATIONAL INSTRUMENTS

 

These are instruments that have been operational in the past, and could be made operational if required for research.

 

Low Temperature Diffractometer

This instrument is based on an INEL 1D position sensitive detector (the CPS120) which can collect X-rays over a 120° arc. For each incident X-ray the detector produces a voltage pulse proportional to the position of the interaction along the knife edge. This is measured using an EG&G Ortec MCA which provides 8K channels giving a 2theta resolution of 0.015°. The sample can be rocked over +/-45° with a resolution of 0.001°.

It incorporates a He chiller (driven by a Leybold LTC 60 temperature controller) enabling temperatures as low as 10K to be routinely reached. The cryostat and rocking system was built in the workshops of the Department of Earth Sciences. Both sample movement and the chiller are computer controlled over an IEEE interface, from software written in-house, enabling automated runs to be setup which may last several days. 

To convert these spectra to other formats see the wconvert program.

High temperature DMA-XRD system

This system is based on an INEL 1D position sensitive detector and specimens can be heated to c. 750c  A Eurotherm 815 temperature controller is used for sample heating. The addition of a Perkin Elmer DMA7 makes this a unique  instrument. Collection of x-rays can be phase locked onto the dynamic force applied by the DMA so that  x-ray spectra from the deformation and relaxation cycles can be collected independently. The 8K channels of the x-ray spectrum allows a 2theta resolution of 0.015°

To convert these spectra to other formats see the wconvert program. 

Richard J. Harrison, Simon A. T. Redfern, Andrew Buckley, and Ekhard K. H. Salje
Application of real-time, stroboscopic x-ray diffraction with dynamical mechanical analysis to characterize the motion of ferroelastic domain walls
J. Appl. Phys. 95, 1706 (2004); DOI:10.1063/1.1639949

 

Calorimeter - diffractometer

This instrument allows x-ray spectra to be collected at the same time as calorimetric measurements. Using this approach the thermal and structural anomalies associated with structural phase transitions can be recorded simultaneously, allowing comparisons to be made without the ambiguities which can arise from independent apparatus having slightly different temperature calibrations.

The calorimeter uses two fluxmeters connected to a thermal reservoir, and ramps the sample temperature continuously between 10 K and room temperature. The x-ray data is recorded using an INEL 1D position sensitive detector (the CPS120) which can collect X-rays over a 120° arc. The 8K channels giving a 2theta resolution of 0.015°. The sample can be rocked in steps of 0.006°.

The Leybold He cooling unit (driven by a Oxford Instruments ITC 601 temperature controller) allows temperatures as low as 40K to be routinely reached. 

The cryostat and rocking system was built in the workshops of the Department of Earth Sciences. Both sample movement and the chiller are computer controlled over an IEEE interface, from software written in-house, enabling automated runs to be setup which may last several days.  

To convert these spectra to other formats see the wconvert program. 

S Hayward, E Salje, T Abraham, C Morrison, A Buckley and S Redfern
A simultaneous X-ray diffractometer / calorimeter for the study of structural phase transitions in solids
J Instrumentation 1 P10006 (2006)  doi: 10.1088/1748-0221/1/10/P10006   

 

4) Surface diffractometer

This instrument, referred to as the "minty" or surface diffractometer, originally had a Siemens 2D X-ray detector (as shown on the sketch below) but this has been replaced by an INEL 1D position sensitive detector. The goniometer platform is a Siemens unit but the specimen translation and rocking system was built in the workshops of the Department of Earth Sciences and experimental setup is controlled from software written in-house. The 8K channels of the x-ray spectrum allows a 2theta resolution of 0.015°. The sample rocking has a resolution of 0.02°.

To convert these spectra to other formats see the wconvert program. 

gaddshistarxrd.gif
Schematic layout showing the basic geometry of the GADDS and HISTAR diffractometer system developed at Cambridge

 

Salje, EKH (1995) A novel 7-circle diffractometer for the rapid analysis of extended defects in thin films, single crystals and ceramics. Phase Transitions 55, 37-56.

 

 Full safety procedures for Cambridge users.


 

 

Last updated on 28-Nov-12 10:05

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