X-Ray Diffraction Applied to the Study of Defects in Surfaces

1984 ◽  
Vol 41 ◽  
Author(s):  
I. K. Robinson ◽  
K. L. D'amico
Keyword(s):  
Long Range ◽  
Domain Walls ◽  
Surface Structures ◽  
Long Range Order ◽  
X Ray Diffraction ◽  
X Ray ◽  
Line Defects ◽  
Reconstructed Surface ◽  
Regular Arrays

AbstractThe role of x-ray diffraction in characterising defects in crystals is reviewed briefly. It is most sensitive to the presence of plane defects which destroy the long-range order. The same argument is shown to apply to line defects in surface structures. Two recent glancing incidence x-ray diffraction experiments provide contrasting examples: randomly distributed steps are found in the Au(110) reconstructed surface, while regular arrays of domain walls modify certain phases of krypton monolayers physisorbed on graphite substrates.

scholarly journals Zur Darstellung und Kristallstruktur von β-NbO2 / Synthesis and Crystal Structure of β-NbO2

1982 ◽  
Vol 37 (11) ◽  
pp. 1361-1368 ◽  
Author(s):  
H.-J. Schweizer ◽  
Reginald Gruehn
Keyword(s):  
Crystal Structure ◽  
Long Range ◽  
Chemical Transport ◽  
Range Order ◽  
Long Range Order ◽  
X Ray Diffraction ◽  
Synthesis And Crystal Structure ◽  
Space Group ◽  
X Ray ◽  
Lattice Constants

By using chemical transport reactions with various transporting agents (HgCl2, NbCl5, Nb3O7Cl) a slightly substoiehiometric NbO2-phase, β-NbO2, was obtained from samples with O/Nb ∼ 1.5 (source; T > 1373 K) and with deposition temperatures > 1273 K (sink). The rango of composition of β-NbO2 was found to exist from NbO1.990 to NbO1.998.The structure of the tetragonal, column-shaped black crystals was determined by X-ray diffraction. It crystallizes tetragonally in the space group I41 with lattice constants a = 9.693(3) Å, c = 5.985(1) Å and Z = 10 formula units.The crystal structure of β-NbO2 is shown to be a deformed rutile type. As in α-NbO2 the Nb-atoms are grouped in pairs. However, both oxides are different with respect to their long-range order.

Anomalous x-ray diffraction measurements of long-range order in (001)-texturedL10FePtCu thin films

2012 ◽  
Vol 86 (2) ◽  
Author(s):  
M. Maret ◽  
C. Brombacher ◽  
P. Matthes ◽  
D. Makarov ◽  
N. Boudet ◽  
...  
Keyword(s):  
Thin Films ◽  
Long Range ◽  
Range Order ◽  
Long Range Order ◽  
X Ray Diffraction ◽  
X Ray

High-Resolution Small-Angle X-Ray Diffraction Study of Long-Range Order in Hard-Sphere Colloidal Crystals

2002 ◽  
Vol 88 (20) ◽  
Author(s):  
A. V. Petukhov ◽  
D. G. A. L. Aarts ◽  
I. P. Dolbnya ◽  
E. H. A. de Hoog ◽  
K. Kassapidou ◽  
...  
Keyword(s):  
High Resolution ◽  
Diffraction Study ◽  
Long Range ◽  
Small Angle ◽  
Hard Sphere ◽  
Colloidal Crystals ◽  
Range Order ◽  
Long Range Order ◽  
X Ray Diffraction ◽  
X Ray

Characterization of Interfacial Structure of InGaAs/InP Short Period Superlattices by Raman Scattering and High Resolution X-Ray Diffraction

1993 ◽  
Vol 324 ◽  
Author(s):  
Teruo Mozume
Keyword(s):  
Raman Scattering ◽  
Long Range ◽  
Range Order ◽  
Interfacial Structure ◽  
Long Range Order ◽  
X Ray Diffraction ◽  
X Ray ◽  
Gas Source ◽  
Short Period ◽  
Short Period Superlattices

AbstractThe x-ray diffraction (XRD) of InGaAs/InP short-period superlattices (SPSL's) grown on (001)InP substrates by gas source molecular beam epitaxy (GSMBE) and by gas source migration enhanced epitaxy (GSMEE) shows that the GSMBE grown SPSL is strain free, and that GSMEE grown SPSL's with InGa-P and In-As heterointerfaces have strain-induced zerothorder satellite peak shift consistent with that in simulation results for the InGaAs/InP SPSL with one monolayer of InGaP and InAs inserted in each interface. Partial destruction of the long-range order is confirmed by the observation of the extra diffraction peak in GSMBE grown SPSL and by weak intensity of satellite peaks and nonuniform spacing between satellite peaks in GSMEE grown SPSL's. Raman scattering shows that the strain is accommodated in the interface layer in GSMEE grown samples. A confinement model without interface disorder fits the GaAs LO phonon very well. These results indicate that the local atomic arrangements are tailored by GSMEE, but that long range-order is impaired by the misfit dislocations in GSMEE grown SPSL's and by the exchange between As to P at the interfaces in GSMBE grown SPSL.

Comparison of temperature driven ordering in bulk foil and thin film of L10ordered FePd

2004 ◽  
Vol 842 ◽  
Author(s):  
Chaisak Issro ◽  
Wolfgang Püschl ◽  
Wolfgang Pfeiler ◽  
Bogdan Sepiol ◽  
Peter F. Rogl ◽  
...  
Keyword(s):  
Thin Film ◽  
Electrical Resistivity ◽  
Long Range ◽  
Molecular Beam ◽  
Resistivity Measurement ◽  
Range Order ◽  
Electrical Resistivity Measurement ◽  
Long Range Order ◽  
X Ray Diffraction ◽  
X Ray

ABSTRACTChanges in the degree of long-range order of 10 μm thick FePd foil are presented and compared with results on 50 nm thick FePd films. The films were produced by dc and rf magnetron co-sputtering on Si as well as by molecular beam epitaxy co-deposition on MgO substrates. Long-range order was studied by electrical resistivity measurement, X-ray diffraction and Möβbauer spectroscopy.

scholarly journals ANALISIS PERBANDINGAN PARAMETER LONG-RANGE ORDER SEBAGAI ACUAN KONTROL KUALITAS HASIL ANNEALING PASCA ECAP PADA Al-5052

2017 ◽  
Vol 39 (2) ◽  
pp. 63
Author(s):  
R. Ibrahim Purawiardi
Keyword(s):  
Long Range ◽  
Range Order ◽  
Long Range Order ◽  
X Ray Diffraction ◽  
X Ray

Telah dilakukan analisis perbandingan parameter long-range order dalam satu sudut pandang pada logam paduan Al-5052 yang diberikan perlakuan ECAP dan annealing pasca ECAP. Sudut pandang yang dipakai adalah sudut pandang tegak lurus bidang (220). Dalam analisis, bidang fundamental adalah bidang (111), sementara bidang superlattice diasumsikan bidang (220). Terdapat 4 sampel uji Al-5052 yang digunakan. Keempat sampel diberikan perlakuan ECAP rute Bc sebanyak 4 pass. Kemudian, 3 dari 4 sampel diberikan perlakuan annealing pasca ECAP dengan variasi temperatur annealing 100 oC, 200 oC, dan 300 oC, sementara satu sampel tersisa sebagai kontrol pembanding. Karakterisasi dilakukan dengan analisis x-ray diffraction. Hasil analisis menunjukkan nilai parameter order sampel tanpa annealing, sampel dengan temperatur annealing 100 oC, sampel dengan temperatur annealing 200 oC, dan sampel dengan temperatur annealing 300 oC secara berturut-turut adalah 0.54526, 0.693152, 0.92553, dan 1.183165. Dengan demikian, terjadi perubahan kondisi dari kondisi lebih disordered menjadi lebih ordered akibat perlakuan annealing pasca ECAP. Sementara itu, kondisi fully ordered diprediksi terjadi saat penerapan temperatur annealing 226.065704 oC. Dari studi ini dapat disimpulkan bahwa metode perbandingan parameter order ini dapat digunakan sebagai acuan kontrol kualitas logam paduan Al-5052 setelah proses annealing pasca ECAP. Namun, analisis ini tidak direkomendasikan untuk menentukan nilai mutlak parameter order, namun hanya direkomendasikan untuk dibandingkan antar sampel satu sama lain.

Imaging of Ferroelectric Domains in KTiOPO4 Single Crystals by Synchrotron X-RAY Topography

1993 ◽  
Vol 310 ◽  
Author(s):  
S. Wang ◽  
M. Dudley ◽  
L.K. Cheng ◽  
J.D. Bierlein ◽  
W. Bindloss
Keyword(s):  
Domain Wall ◽  
Single Crystals ◽  
Long Range ◽  
Domain Walls ◽  
Three Dimensional ◽  
Dynamical Theory ◽  
X Ray Diffraction ◽  
X Ray ◽  
Domain Structures ◽  
Main Components

AbstractThe application of synchrotron white beam X-ray topography to the study of ferroelectric domain structures in hydrothermally grown potassium titanyl phosphate (KTiOPO4: KTP) single crystals is reported. The domain walls can be exclusively imaged on topographs with selected diffraction vectors and X-ray wavelengths, while images of other defects, such as dislocations, inclusions and surface scratches, can be simultaneously made very diffuse. The topographic images correspond well with electrostatic toning images. X-ray topography readily reveals the three dimensional shapes of the domain walls. There are two contributions to domain wall contrast: one is fringe-like which can be interpreted in terms of the dynamical theory of X-ray diffraction, and the other is diffuse strain contrast arising from long range strain associated with the wall. These two contributions can be observed simultaneously or separately depending on the diffraction conditions. The long range strain is thought to be associated with the curvature of the domain walls. It appears that the main components of the displacement field associated with this strain are directed approximately perpendicular to the domain wall.

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