Using%20Diffractometers%20in%20SPEC

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Using Diffractometersin SPEC
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Geometries

• fourc, kappa
• fivec,
• sixc, psic
• twoc,
• w21v, w21h
• s1d2, s2d2
• zaxis
• .

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Reminder

• Diffractometer working in crystal coordinates
  HKL
• H,K,L to motor positions matrix UB
• A particular geometry gives different modes of
  operation.
• Motor names are fixed by the geometry
• ( and always first in wa magic! )

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A diffraction experiment

• Enter lattice parameters setlat
• Defining orientation matrix
• setor0, setor1, or0, or1
• Deciding working mode
• setmode, freeze
• setsector
• and work
• wh, ca, ci,pa, hklscan,kscan...

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Operation Modes

• Use modes to fix some conditions
• freeze

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Orientation Matrix

• or0, or1 ( setor0, setor1 )
• can be entered manually enterUB
• or by refinement ( several reflexions )
• reflex_beg
• reflex
• reflex_end
• You can print it

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Usage

• pa ( show current settings )
• wh ( show h,k,l and motor positions )
• ca, ci ( calculates and show, no move )
• br ( go to brag 1,0,1)

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Scans ( of course )

• hklscan and variants
• hscan
• kscan
• lscan
• Radial scans ( follow a line )
• hkradial, hlradial, klradial
• Circular scans ( doing an arc )
• hkcircle, hlcircle, hkcircle

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More

• Save
• will put all parameters into a file
• load it with do filename

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Internals

• calcA
• calculates A from HKL
• calcHKL
• calculates HKL from A
• leaves values in H,K and L
• Who said pseudo-motors?