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X-ray techniques. Basic Introduction. Alla Arakcheeva. X-ray techniques. Basis introduction. X-rays is the most important discovery in recent history Who have enlightened our world ? Sources of X-rays Interaction of X-rays and matter
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X-ray techniques Basic Introduction Alla Arakcheeva
X-ray techniques. Basis introduction • X-rays is the most important discoveryin recent history • Who have enlightened our world? • Sources of X-rays • Interaction of X-rays and matter • Methods based on X-ray spectroscopy (XRS) • Methods based on X-ray diffractometry (XRD) • Using synchrotron radiation • Synchrotron or home laboratory?
The X-ray has been voted as the most important discovery in recent history … by 50’000 participants in a British Science Museum poll, which had been carried out in 2009 • The X-ray machine • Penicillin • The DNA double helix … • “X-rays have radically changed the way we see and understand our world” • “X-rays allowed to look inside without any damage of solids and to see a human body without any operation”
Who have enlightened our world? Beginners • 1895Wilhelm KonradRoentgen discovered and described properties of new rays, which he called X-rays 1901 The First Nobel Prize for Physics He held a demonstration with his first X-Ray pictures, along with one of his wife's hand.
Who have enlightened our world? Beginners • 1899 H. Haga and C. Wind discovered the X-Rays diffraction by a slit The X-rays are electromagnetic waves with l~ 1 Å
Who have enlightened our world? Beginners • 1904 Charles Barkla discovered the secondary (characteristic) X-ray radiation of elements, which depends on their atomic weight 1917 Nobel Prize in Physics K Decelerated or «braking» or «white» X-ray radiation
Who have enlightened our world? Beginners • 1912 Max von Laue discovered diffraction of X-rays by crystals Laue’s equations: S . a = n1 (integer) S . b = n2 (integer) S . c = n3 (integer) S - scattering vector a, b, c - lattice vectors { 1914 Nobel Prize in Physics
Who have enlightened our world? Beginners • 1912 Sir William Lawrence Bragg derived Bragg's Law
Who have enlightened our world? Beginners • 1915 SirWilliam Henry Bragg andWilliam Lawrence Bragg jointly received Nobel Prize in Physics "for their services in the analysis of crystal structure by means of X-rays” Start of X-ray crystallography: C (diamond), NaCl, KCl, KBr, KI, CF2, ZnS, FeS2, CaCO3, …
26 Nobel Prizes were awarded for achievements related to X-ray techniques • … • 2009 Chemistry V. Ramakrishnan, T.A. Steitz, A.E. Yonath Studies of the structure and function of the ribosome • 2011 Chemistry Daniel Shechtman "for the discovery of quasicrystals" Ribosome
X-rays • X-rays are electromagnetic waves, l ~ 10-11 – 10-8 m • X-rays appear when electrons are accelerating or decelerating • X-rays interact with electrons
Sources of X-rays 1. X-ray tubes operate in laboratory devices Scheme X-rays Thermo-emitted electrons Water cooling system Voltage cathode heating Accelerating voltage Ua ~ 50kV
Sources of X-rays 2. Synchrotron radiation The X-ray flux is 104 – 106 times more intense than in the X-ray tube
Sources of X-rays European Synchrotron radiation Facility (ESRF), Grenoble: Energy of one beam 6 GeV Accelerator of electrons Beam lines Circumference 844 m
Sources of X-rays European Synchrotron radiation Facility (ESRF), Grenoble: Energy of one beam 6 GeV A single beam line
Sources of X-rays European Synchrotron radiation Facility (ESRF), Grenoble: Energy of one beam 6 GeV A management team Experimental facilities A single beam line
Sources of X-rays European Synchrotron radiation Facility (ESRF), Grenoble: Energy of one beam 6 GeV
Sources of X-rays European Synchrotron radiation Facility (ESRF), Grenoble: Energy of one beam 6 GeV 41 beam-lines are managed by 19 countries
Sources of X-rays European Synchrotron radiation Facility (ESRF), Grenoble: Energy of one beam 6 GeV Inside of a beam line
Basis of X-ray analysis Interaction of X-rays and matter Diffraction Inelastic interactions Elastic scatering Methods based on X-ray diffractmetry (XRD) Methods based on X-ray spectrometry (XRS)
Method based on X-ray spectroscopy (XRS) • X-ray fluorescence spectroscopy • X-ray tomography • Extended X-ray absorption spectrometry (EXAFS)
Method based on X-ray spectroscopy (XRS) • X-ray fluorescence spectroscopy • X-ray tomography • Extended X-ray absorption spectrometry (EXAFS)
How it works (ESRF, Grenoble) Scheme 3µm Silicon chip stacking in microelectronics
Method based on the X-ray spectroscopy (XRS) • X-ray fluorescence spectroscopy • X-ray tomography • Extended X-ray absorption spectrometry (EXAFS)
How it works (ESRF, Grenoble) Local structure vs Oxygen Storage Capacity in mixed oxides Nagai et. Al. Catalysis Today (2002)
Metod based on X-ray diffraction (XRD) • Single crystal and powder XRD Diffraction • X-ray topography • Small and Wide-Angle Scattering (SAXS/WAXS)
The universal method for discovery ! W. H. Bragg and W. L. Bragg Nobel Prize in 1915 V. Ramakrishnan, T. A. Steitz, A. E. Yonath Nobel Prize in 2009 NaCl Ribosome
Single crystal XRD Typical study Confirmation of expected structure of a new small molecule compound A new second-order nonlinear optical material4-bromo-4’nitrobenzylidene aniline (BNBA), C13H9BrN2O2
Single crystal XRD Typical study Confirmation of expected structure of a new small molecule compound 18’234 measured reflections; T = 173 K Single crystal 4-bromo-4’nitrobenzylidene aniline (BNBA), A new second-order nonlinear optical material
Single crystal XRD Typical study Confirmation of expected structure of a new small molecule compound • Expected result: monoclinic crystallographic system • UnexpectedResult: Non-traditional, (3+1)Dsymmetry – A2(a0g)0 h Hhklm = ha* + kb* + lc* + mq (de Wolff, P.M. , 1974) Satellites q H4001 H4000 mtw l Bragg’s reflections Hhkl = ha* + kb* + lc* (W. L. Bragg, 1912)
Single crystal XRD Typical study Confirmation of expected structure of a new small molecule compound • Expected result: Structure of the small molecule 4-bromo-4’nitrobenzylidene aniline (BNBA), A new second-order nonlinear optical material
Single crystal XRD Typical study Confirmation of expected structure of a new small molecule compound • Expected result: H-bonds between molecules • UnexpectedResult: Aperiodic distribution of the H-bonds 4-bromo-4’nitrobenzylidene aniline (BNBA), A new second-order nonlinear optical material
Single crystal XRD Typical study Confirmation of expected structure of a new small molecule compound • Unexpected Result: Splitting of molecule at 293 K 4-bromo-4’nitrobenzylidene aniline (BNBA), A new second-order nonlinear optical material
Powder XRD • Typical tasks • Degree of crystallinity Time of annealing 0 180 Diffraction (scattering) angle 2q
Powder XRD • Typical tasks • Phase identification • > 600’000 • reference materials • are currently listed in the • Powder Diffraction File • Database Identification of (NH4)6(NiMo9O32).6H2O Experimental profile and Referred lines from PDF 77-1734
Powder XRD • Typical tasks • Crystal structure determination • and refinement BiCu5O3S BiOCuS Bi (known), BiOCuS (known), BiCu5O3S (unknown before) !
Powder XRD • Typical tasks • Phase analysis • quantitative & qualitative 1 2 Paint sample from ancient Ethiopian icons 1 2
Powder XRD • Typical tasks • Anisotropic micro-strain distribution KSm(MoO4)2 Isotropic micro-strain line broadening boadening Anisotropic micro-strain line broadening The anisotropic micro-strain distribution is the origin of the anisotropic line broadening
Methods based on X-ray diffraction (XRD) • Single crystal and powder XRD Diffraction • X-ray topography • Small and Wide-Angle Scattering (SAXS/WAXS)
X-ray diffraction imaging or X-ray-topography • Objects • nearly perfect crystals How it works at ESRF (Grenoble)
Methods based on X-ray diffraction (XRD) • Single crystal and powder XRD Diffraction • X-ray topography • Small and Wide-Angle Scattering (SAXS/WAXS)
How it works Solid Submelted Randomly aligned domains Recrystallized µm and nm scales of analyzed object Scattering angles: 0.1 – 10o Preferentially aligned domains
Micro / nano X-ray diffraction using synchrotron radiation(ESRF) • Specific features • Non-destructive techniques • High flux • X-ray energy: typical 8-24 keV • up to 100 keV at HE beamline • Focused beam (100 nm) • Scanning diffraction with • spatial resolution • Micro/nano size of analyzed object • (down to 100 nm) • Applications • Single polymer fiber diffraction • Scanning diffraction of polymer films • Grazing incidence micro-diffraction on surfaces • Chemical micro-crystallography • Structure of Individual powder grain
Synchrotron or home laboratory? Synchrotron laboratory Home Laboratory • Higher resolution • Higher flux • Quick counting times in experiments • Precise characterization of a local • area (down to nano scale) • Lower overall cost of a study • Ease accessibility • Easy to use • Quick average characterization of • a large volume (down to µm scale) • Advanced and precise study • General and average characteristics • Use synchrotron radiation • if you are ready • Toexplore • new fields • To reconsider • some theories • Use laboratory devices • if you are going • To confirm • traditional views • To add a new item • to a well known list