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Calculation dependence of shift and size of the sample for X-ray diffraction and SANS. Supervisor Dr A. I. Kuklin. Rafał Idczak University of Wrocław. JINR Summer Student Practicies 2010, Dubna. The goal of the project at JINR Dubna summer practice. - PowerPoint PPT Presentation
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Calculation dependence of shift and size of the sample for X-ray diffraction and SANS
SupervisorDr A. I. Kuklin
Rafał IdczakUniversity of Wrocław
JINR Summer Student Practicies 2010, Dubna
The goal of the project at JINR Dubna summer practice
1 – recalculation of angles in XPD method
2 – determination of nanodiamonds lattice parameters
3 – determination of nanodiamonds size of domains
4 – estimation of influence of sample size on resolution in SANS
5 – comparison between the SANS spectrometers with and without TOF method
Recalculation angles in XPD
cos
cos
sintan
L
L
2cos
tan
cossin
L
Recalculation for Al2O3
Recalculation for Al2O3
Number of peak α + β 2α
1 34.433 35.1462 37.020 37.7713 42.513 43.347
2costan
cossin
L
019.0L
Recalculation for nanodiamonds
Number of peak α + β 2α
1 43.017 43.897
2 74.208 75.909
3 90.059 92.331
Nanodiamonds size of domains
cos
FK
Scherrer equation
K – shape factor (K = 1)F – FWHMθ – Bragg angle (2θ = 2α)λ – wavelength (λ = 1.5405 Å)τ – mean size of domains
Number of peak FWHM θ τ [Å]
1 1.9828 21.729 47.919
2 2.3381 37.529 47.608
3 2.2535 45.598 55.978
Estimation of influence of sample size on resolution in SANS
L
d tantan
Ld
tan
tan
for , 0
d = 5 – 20 mm
L = 2 – 12 m
= 0.7 – 10 Å
12
sin4
2sin
4
Ld
Qres
Q resolution for λ = 0.7 Å
Q resolution for λ = 5 Å
Q resolution for λ = 10 Å
YuMO - Frank Laboratory of Neutron Physics, Joint Institute of Nuclear Physics, Dubna, Russia.
1, 2, 3 – pulse reactor parts4, 6 – collimators5 – vacuum tube7 – thermostate8 – table for sample10, 11 – Vn standards12 - 14 – detectors
D11 – Institute Laue-Langevin, Grenoble, France
Main differences between YuMO and D11
1 – D11 has got 1 PSD detector, YuMO has got 2 detectors2 – YuMO has got Vanadium standard before detectors3 – YuMO hasn’t got neutron guide (vacuum tube)
Comparison of the main feature of SANS spectrometers with and without TOF
YuMO D11With TOF
↓Wavelength resolution (1%)
Without TOF↓
Wavelength resolution (5-10%)
Pulsed reactor source↓
Power of the flux 2 MW
Continuous reactor source↓
Power of the flux 50 MW
Two detectors system↓
Better dynamic Q rate (Qmax/Qmin)
Power of the flux + neutron guide + collimation
↓Better Q-range and background
Vanadium standards before detectors↓
Calibration during measurements
Additional calibration measurements needed
Conclusions1 – It was shown that continuous and pulsed sources have both advantages and disadvantages in characteristics of main features
2 – We obtained the mean size of domains for nanodiamonds sample is 50.5(2.7) Å.
3 – We calculated that resolution dependence of size d of the measured sample in SANS experiment is also dependent of L and .
d ↑ Qres ↓
L ↑ Qres ↑
λ ↑ Qres ↑
Special thanks to:
Dr A. I. Kuklin (FLNP, JINR, Dubna)
Dr S. Z. Pakuliak (BLTP JINR, Dubna)
Dr W. Chmielowski (JINR, Dubna)
Dr hab. R. Zawodny (UAM, Poznań)
Thank you for attention
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