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Set Axis Motions:  Two buttons on the Goniometer Setting of the RINT/Rapid screen marked MODE also must be set for your experiment.  Different specimen characteristics will affect these choices  

Omega-axis:  You must choose between “Fixed” and “Oscillation.”  Generally, when working with fragments of crystals oscillation should be chosen with a good range being  15<φ<40 for which collision of the X-Y stage with the Beam Stop is not a concern.

Again, Oscillation with 15<φ<40 is good, but 20<φ<60 can be used with caution

For speed, and exposures longer than 5 minutes, 1 degree/minute is fine.

Phi-axis:  You must choose betweenFixed and Oscillation” and “Spin.”  Again, when working with fragments, oscillation or spin are appropriate.  There is the potential for a collision of the sample set screw with the Beam Stop at higher values of Omega, so setting oscillation from –180 to 0 degrees will provide maximum randomicity for a “powder pattern.”

Again, Oscillation with 180<φ<0 is good, but Spin can be used with caution

For speed, and exposures longer than 5 minutes, 3 degree/minute is fine.

Do a Test Run if this is the first time you have used these settings.

Press the Measure / Execute button at bottom of the Rint Rapid Screen.  The finish time of the measurement will appear in the XXX window.  Jump to Observations paragraph, below.

Measurements on “solid surfaces” samples:

Solid samples include thin sections, polished sections, rock fragments, pot shards, etc.  All of these BUT thin sections will completely absorb the direct X-ray beam and do not require the BEAM STOP.  Thin Section require using the Long Beam Stop.

Extra instructions for X-raying surfaces:  Surface analysis of rocks and other coarsely crystalline samples is improved by rotating on PHI, so the surface should be mounted such that it is normal to PHI.  The flat mounting tool as used for observing polished mounts with a microscope in combination with Blu-Tack and a mounting pin or SEM stub is suggested – talk to the management if you are not familiar with this practice.

Set Attachment Stage and Sample Holder Conditions:  Two buttons on the Goniometer Setting of the RINT/Rapid screen marked CHANGE must be set for your experiment.  Different Mounting techniques and specimen aspect ratios require limits to the ranges of OMEGA and PHI.  The following instructions assume samples larger than 1 cm across; otherwise, ask the management for advice.

Attachment Stage:  Set to “Manual-XY-stage.”  

Sample Holder:  Set to “Small Reflection” with a short collimator or “Standard Reflection” with a long collimator.

Set Axis Motions:  Two buttons on the Goniometer Setting of the RINT/Rapid screen marked MODE also must be set for your experiment.  Different specimen characteristics will affect these choices  

Omega-axis:  You must choose betweenFixed and Oscillation.”  

If the sample is cryptocrystalline, a Fixed setting can be chosen at some angle between those listed below.  For more coarsely crystalline sample, Oscillation should be chosen. Generally, when working with a surface there is a competition between getting ω variation large enough to produce many

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