I should point out (because it is not completely intuitive) that if you want to try and characterize trace elements in a compound and only want to measure the trace elements, you must specify the bulk matrix to get a reasonable result. Why? Because the "wheels come off" in the physics model if the total is zero as seen here:
Un 8 RbTiOPO4
TakeOff = 40.0 KiloVolt = 20.0 Beam Current = 100. Beam Size = 0
(Magnification (analytical) = 20000), Beam Mode = Analog Spot
(Magnification (default) = 400, Magnification (imaging) = 400)
Image Shift (X,Y): .00, .00
Pre Acquire String : mag 100000
Post Acquire String : mag 400
Number of Data Lines: 6 Number of 'Good' Data Lines: 6
First/Last Date-Time: 03/23/2015 05:20:27 PM to 03/23/2015 05:57:30 PM
WARNING- Quantitation is Disabled For pt ma, Spectro 2
Average Total Oxygen: .000 Average Total Weight%: .000
Average Calculated Oxygen: .000 Average Atomic Number: 10.800
Average Excess Oxygen: .000 Average Atomic Weight: .000
Average ZAF Iteration: .00 Average Quant Iterate: 1.83
WARNING- Duplicate analyzed elements are present in the sample matrix!!
Use Aggregate Intensity option or Disable Quant feature for accurate matrix correction.
Un 8 RbTiOPO4, Results in Elemental Weight Percents
SPEC: Rb Ti P O
TYPE: SPEC SPEC SPEC SPEC
AVER: .000 .000 .000 .000
SDEV: .000 .000 .000 .000
ELEM: Pt Pt
BGDS: LIN LIN
TIME: --- 200.00
BEAM: --- 100.02
ELEM: Pt-D Pt SUM
XRAY: (ma) (la)
313 --- .00000 .00000
314 --- .00000 .00000
315 --- .00000 .00000
316 --- .00000 .00000
317 --- .00000 .00000
318 --- .00000 .00000
AVER: --- .00000 .00000
SDEV: --- .00000 .00000
SERR: --- .00000
%RSD: --- .00000
STDS: --- 578
STKF: --- .9954
STCT: --- 176.27
UNKF: --- .0000
UNCT: --- .01
UNBG: --- 1.69
ZCOR: --- 1.0000
KRAW: --- .00005
PKBG: --- 1.00548
Note that all the inputs look reasonable and the matrix correction is 1.0 by default, but nothing happens during the iteration.
However, if we simply specify the matrix elements (in CalcZAF just click an empty element row, in Probe for EPMA just click the Specified Concentrations button in the Analyze window! window) we will get a non-zero amount as seen here:
Un 8 RbTiOPO4
TakeOff = 40.0 KiloVolt = 20.0 Beam Current = 100. Beam Size = 0
(Magnification (analytical) = 20000), Beam Mode = Analog Spot
(Magnification (default) = 400, Magnification (imaging) = 400)
Image Shift (X,Y): .00, .00
Pre Acquire String : mag 100000
Post Acquire String : mag 400
Number of Data Lines: 6 Number of 'Good' Data Lines: 6
First/Last Date-Time: 03/23/2015 05:20:27 PM to 03/23/2015 05:57:30 PM
WARNING- Quantitation is Disabled For pt ma, Spectro 2
Average Total Oxygen: .000 Average Total Weight%: 100.007
Average Calculated Oxygen: .000 Average Atomic Number: 21.780
Average Excess Oxygen: .000 Average Atomic Weight: 30.545
Average ZAF Iteration: 1.33 Average Quant Iterate: 1.83
WARNING- Duplicate analyzed elements are present in the sample matrix!!
Use Aggregate Intensity option or Disable Quant feature for accurate matrix correction.
Un 8 RbTiOPO4, Results in Elemental Weight Percents
SPEC: Rb Ti P O
TYPE: SPEC SPEC SPEC SPEC
AVER: 34.979 19.604 12.676 32.741
SDEV: .000 .000 .000 .000
ELEM: Pt Pt
BGDS: LIN LIN
TIME: --- 200.00
BEAM: --- 100.02
ELEM: Pt-D Pt SUM
XRAY: (ma) (la)
313 --- .00802 100.008
314 --- .01363 100.014
315 --- .02540 100.025
316 --- .00045 100.001
317 --- -.01496 99.9851
318 --- .00934 100.009
AVER: --- .00698 100.007
SDEV: --- .01352 .01352
SERR: --- .00552
%RSD: --- 193.632
STDS: --- 578
STKF: --- .9954
STCT: --- 176.27
UNKF: --- .0001
UNCT: --- .01
UNBG: --- 1.69
ZCOR: --- 1.3400
KRAW: --- .00005
PKBG: --- 1.00548
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