magnettech SPE file in ES 5.2.11

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elpelta
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Joined: Mon Jan 15, 2018 2:19 pm

magnettech SPE file in ES 5.2.11

Post by elpelta »

Hello,

For evaluation, my spectra were simulated very well using easyspin version 5.1.11. This year, I downloaded the new easyspin version (5.2.11) and opened the same matlab files (R2016a) and my simulated spectra was shifted and do not fits to my experimental spectra anymore. My samples were measured using EPR spectrometer MS400 (Magnettech) and my spectra have .spe format. Is it possible that the simulation of .spe files could be influenced by new easyspin version? Does somebody know, what was changed in the new easyspin version?

I would be very thankful about your help.
Stefan Stoll
EasySpin Creator
Posts: 1041
Joined: Mon Jul 21, 2014 10:11 pm
Location: University of Washington

Re: magnettech SPE file in ES 5.2.11

Post by Stefan Stoll »

There were some changes to the SPE loader. Look at the data with the magnettech software and compare the magnetic-field axis to the one obtained with EasySpin's eprload(). If they are inconsistent with the current version, please post the data so we can have a look.
elpelta
Newbie
Posts: 4
Joined: Mon Jan 15, 2018 2:19 pm

Re: magnettech SPE file in ES 5.2.11

Post by elpelta »

For better understanding, I attachted images of my experimental/simulated spectra in 1. MPlot (MS400 software), 2. Easyspin version 5.1.11 and 3. Easyspin version 5.2.11 as well as the associated .spe file.

The magnetic field axis in the Magnettech software is different to the Easyspin one (both version). But the magnetic field of the experimental spectrum also differs in the both easyspin version. The illustration of the simulated spectrum is in both Easyspin version the same. So, it seems that the experimental spectrum (.spe format) is illustrated in the new easy spin version in an other way compared to the old one. I have the same problem in all my files so far.

Do you know what I can change in my mathlab file to obtain the experimental spectrum in the new version that looks in the same way as in the old version?

I would be thankful for your help.
Attachments
3. Experimental_simulated Spectrum Easyspin v.5.2.11.png
3. Experimental_simulated Spectrum Easyspin v.5.2.11.png (59.52 KiB) Viewed 1993 times
2. Experimental_simulated Spectrum Easyspin v.5.1.11.png
2. Experimental_simulated Spectrum Easyspin v.5.1.11.png (55.71 KiB) Viewed 1993 times
1. Experimental Spectrum in MPlot.png
1. Experimental Spectrum in MPlot.png (32.55 KiB) Viewed 1993 times
elpelta
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Posts: 4
Joined: Mon Jan 15, 2018 2:19 pm

Re: magnettech SPE file in ES 5.2.11

Post by elpelta »

The .spe file
Attachments
20160530_Experimental spectrum.Spe
(8.06 KiB) Downloaded 250 times
Stefan Stoll
EasySpin Creator
Posts: 1041
Joined: Mon Jul 21, 2014 10:11 pm
Location: University of Washington

Re: magnettech SPE file in ES 5.2.11

Post by Stefan Stoll »

This inconsistency is puzzling. What are the settings for the center field and for the sweep width in the MS400 software? The latest EasySpin version gives:

Code: Select all

>> [B,spc,par] = eprload('20160530_Experimental spectrum.Spe'); par
par = 
  struct with fields:

          B0_Field: 335.0831
           B0_Scan: 6.8575
        Modulation: 0.2000
    MW_Attenuation: 10
          ScanTime: 30
              Gain: 200
            Number: 1
        Time_const: 0
     NumberSamples: 4096
       Temperature: []
         FileFlags: 2
            mwFreq: []
Are all the other parameters (attenuation etc.) consistent with what is shown in the MS400 software?
elpelta
Newbie
Posts: 4
Joined: Mon Jan 15, 2018 2:19 pm

Re: magnettech SPE file in ES 5.2.11

Post by elpelta »

I checked the parameters in my easyspin version and in the MS400 software. They are all in accordance with your parameters of the latest EasySpin version.
Attachments
MS400.PNG
MS400.PNG (28.53 KiB) Viewed 1971 times
Stefan Stoll
EasySpin Creator
Posts: 1041
Joined: Mon Jul 21, 2014 10:11 pm
Location: University of Washington

Re: magnettech SPE file in ES 5.2.11

Post by Stefan Stoll »

Excellent. Then ES 5.2.11 and the magnettech software are consistent with regards to the field range. Prior to ES 5.2, the field axis was loaded incorrectly in some cases like yours.

Here is the background: magnettech actually has two SPE file formats, an "old" one and a "new" one, that are used on different spectrometers and different acquisition software versions. The old and new format differ in how parameters such as the center field and the sweep range are stored. Prior to 5.2, ES read all SPE files assuming the old format. Your file is in the new format. Since 5.2, ES is able to detect which format is used.

(I have renamed this post so that other users can find this when they run into the same issue.)
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