X-ray scattering in disordered structures and imperfects crystals Sylvain Ravy Laboratoire de...
-
Upload
bernard-charlet -
Category
Documents
-
view
106 -
download
1
Transcript of X-ray scattering in disordered structures and imperfects crystals Sylvain Ravy Laboratoire de...
![Page 1: X-ray scattering in disordered structures and imperfects crystals Sylvain Ravy Laboratoire de physique des solides bât. 510, Université Paris-sud 91405,](https://reader036.fdocuments.net/reader036/viewer/2022070309/551d9d84497959293b8bfe88/html5/thumbnails/1.jpg)
X-ray scattering in disordered structuresand
imperfects crystals
Sylvain Ravy
Laboratoire de physique des solidesbât. 510, Université Paris-sud91405, Orsay Cedex, France
suite
![Page 2: X-ray scattering in disordered structures and imperfects crystals Sylvain Ravy Laboratoire de physique des solides bât. 510, Université Paris-sud 91405,](https://reader036.fdocuments.net/reader036/viewer/2022070309/551d9d84497959293b8bfe88/html5/thumbnails/2.jpg)
Pair-distribution function density-density
~e(-rou ~r-Peak: Nb of neighbors
Width: fluctuation
Correlation length
![Page 3: X-ray scattering in disordered structures and imperfects crystals Sylvain Ravy Laboratoire de physique des solides bât. 510, Université Paris-sud 91405,](https://reader036.fdocuments.net/reader036/viewer/2022070309/551d9d84497959293b8bfe88/html5/thumbnails/3.jpg)
A crystal is
‘‘Any solid having an essentially discrete diffraction diagram.’’
IUCr
Definition: reciprocal spaceSolid (all crystals solid)
Discrete (indexation)Essentially (disorder 1st type diffuse scattering)
Periodic crystalsIncommensurate crystals
Quasi-crystals
![Page 4: X-ray scattering in disordered structures and imperfects crystals Sylvain Ravy Laboratoire de physique des solides bât. 510, Université Paris-sud 91405,](https://reader036.fdocuments.net/reader036/viewer/2022070309/551d9d84497959293b8bfe88/html5/thumbnails/4.jpg)
Dichalcogénure de tantale :TaSe2
Onde de densité de charge
Microscope à force atomique :Réseau moyen
Microscope à effet tunnel :Onde de densité de charge
![Page 5: X-ray scattering in disordered structures and imperfects crystals Sylvain Ravy Laboratoire de physique des solides bât. 510, Université Paris-sud 91405,](https://reader036.fdocuments.net/reader036/viewer/2022070309/551d9d84497959293b8bfe88/html5/thumbnails/5.jpg)
Cliché de précession d’un cuprate de la famille des supraconducteurs à haut-Tc :
Bi2+xSr2-xCuO6+
Plan (0kl)
b*
c*
1 2 k=3
Espace réciproque indéxé par :
Q=ha*+kb*+lc*+mq
x=0.2 q=0.204(2)b*+0.406(5)c*
x=0.4 q=0.210(4)b*+0.464(7)c*
x=0.6 q=0.223(3)b*+0.332(8)c*
2
4
6
8
10
12
14
l=16
123m=0
(D’après G. Pan, Thèse, Orsay)
![Page 6: X-ray scattering in disordered structures and imperfects crystals Sylvain Ravy Laboratoire de physique des solides bât. 510, Université Paris-sud 91405,](https://reader036.fdocuments.net/reader036/viewer/2022070309/551d9d84497959293b8bfe88/html5/thumbnails/6.jpg)
DIPSI3)0.74 : un liquide unidimensionnel
(Source : P. A. Albouy et al., Phys. Rev. B 35 (1987) 173 )
back
![Page 7: X-ray scattering in disordered structures and imperfects crystals Sylvain Ravy Laboratoire de physique des solides bât. 510, Université Paris-sud 91405,](https://reader036.fdocuments.net/reader036/viewer/2022070309/551d9d84497959293b8bfe88/html5/thumbnails/7.jpg)
High pressure Barium structure
5.5 GPa 12.6 GPa
Phase ICubique centré
Phase IIHexagonal
Phase IVTétragonal inc.
45 GPa
Phase VHexagonal
Phase IV : incommensurateBa Chains inbedded in Ba tetragonal I matrix
= 0.341 nm
R.J. Nelmes, D.R Allan, M.I McMahon, et S.A. Belmonte, Phys. Rev. Lett., 83 (1999) 4081
Ch=0.4696 nm
![Page 8: X-ray scattering in disordered structures and imperfects crystals Sylvain Ravy Laboratoire de physique des solides bât. 510, Université Paris-sud 91405,](https://reader036.fdocuments.net/reader036/viewer/2022070309/551d9d84497959293b8bfe88/html5/thumbnails/8.jpg)
Espace réciproque
Rubidium IV Barium IV
Ch Cg
R.J. Nelmes, D.R Allan, M.I McMahon, et S.A. Belmonte, Phys. Rev. Lett., 83 (1999) 4081
U. Schwarz, A. Grzechnik, K. Syassen, I. Loa et M. Hanfland, Phys. Rev. Lett., 83 (1999) 4085
back
![Page 9: X-ray scattering in disordered structures and imperfects crystals Sylvain Ravy Laboratoire de physique des solides bât. 510, Université Paris-sud 91405,](https://reader036.fdocuments.net/reader036/viewer/2022070309/551d9d84497959293b8bfe88/html5/thumbnails/9.jpg)
Diffraction électronique d’un alliage d’Al-Mn(D’après D. Shechtman et al. Phys. Rev. Lett. 53, 1951 (1984))
![Page 10: X-ray scattering in disordered structures and imperfects crystals Sylvain Ravy Laboratoire de physique des solides bât. 510, Université Paris-sud 91405,](https://reader036.fdocuments.net/reader036/viewer/2022070309/551d9d84497959293b8bfe88/html5/thumbnails/10.jpg)
Platonic Solids
back
![Page 11: X-ray scattering in disordered structures and imperfects crystals Sylvain Ravy Laboratoire de physique des solides bât. 510, Université Paris-sud 91405,](https://reader036.fdocuments.net/reader036/viewer/2022070309/551d9d84497959293b8bfe88/html5/thumbnails/11.jpg)
Axe d ’ordre 2
Axe d ’ordre 3
Axe d ’ordre 5
Alliage d’AlLiCu
D’après Dénoyer et al. (1987)
![Page 12: X-ray scattering in disordered structures and imperfects crystals Sylvain Ravy Laboratoire de physique des solides bât. 510, Université Paris-sud 91405,](https://reader036.fdocuments.net/reader036/viewer/2022070309/551d9d84497959293b8bfe88/html5/thumbnails/12.jpg)
-Image par microscopie électronique haute résolution d’un alliage Al-Fe-Cu, suivant un axe d ’ordre 5
-Premières tuiles d’un pavage de Penrose
D’après M. Audier (1990)
![Page 13: X-ray scattering in disordered structures and imperfects crystals Sylvain Ravy Laboratoire de physique des solides bât. 510, Université Paris-sud 91405,](https://reader036.fdocuments.net/reader036/viewer/2022070309/551d9d84497959293b8bfe88/html5/thumbnails/13.jpg)
Aperiodic Tillings
PENROSE TILLINGAperiodic
5-fold symmetryLocal order
DODECAGONAL TILLINGAperiodic
12-fold symmetryLocal order
![Page 14: X-ray scattering in disordered structures and imperfects crystals Sylvain Ravy Laboratoire de physique des solides bât. 510, Université Paris-sud 91405,](https://reader036.fdocuments.net/reader036/viewer/2022070309/551d9d84497959293b8bfe88/html5/thumbnails/14.jpg)
Liquid crystals - mesophases
-Intermediate states in between solid_liquidOr in between SRO-QLRO-LRO
Orientational order…g(r) is anisotropic
Based on anisotropic molecules: rod-like, disk-like, chiral, amphiphilic
Two sorts of liquid crystals:Thermotropic: change in T
Lyotropic: change in concentration and T
![Page 15: X-ray scattering in disordered structures and imperfects crystals Sylvain Ravy Laboratoire de physique des solides bât. 510, Université Paris-sud 91405,](https://reader036.fdocuments.net/reader036/viewer/2022070309/551d9d84497959293b8bfe88/html5/thumbnails/15.jpg)
Cristaux liquides thermotropes
Téreptal-bis(p-butylaniline) TBBA
Phase liquide isotrope
T=236 °C
Phase nématique
T=200 °C
Phase smectique A
T=175 °C
Phase smectique C
cholesterique
![Page 16: X-ray scattering in disordered structures and imperfects crystals Sylvain Ravy Laboratoire de physique des solides bât. 510, Université Paris-sud 91405,](https://reader036.fdocuments.net/reader036/viewer/2022070309/551d9d84497959293b8bfe88/html5/thumbnails/16.jpg)
Phases hexatiques
Smectique A
a
Smectique B (cristal)
a
a
Hexatique
![Page 17: X-ray scattering in disordered structures and imperfects crystals Sylvain Ravy Laboratoire de physique des solides bât. 510, Université Paris-sud 91405,](https://reader036.fdocuments.net/reader036/viewer/2022070309/551d9d84497959293b8bfe88/html5/thumbnails/17.jpg)
Lyotropic Liquid Crystals
Amphiphilic molecules: Part hydrophobic Part hydrophilic
![Page 18: X-ray scattering in disordered structures and imperfects crystals Sylvain Ravy Laboratoire de physique des solides bât. 510, Université Paris-sud 91405,](https://reader036.fdocuments.net/reader036/viewer/2022070309/551d9d84497959293b8bfe88/html5/thumbnails/18.jpg)
![Page 19: X-ray scattering in disordered structures and imperfects crystals Sylvain Ravy Laboratoire de physique des solides bât. 510, Université Paris-sud 91405,](https://reader036.fdocuments.net/reader036/viewer/2022070309/551d9d84497959293b8bfe88/html5/thumbnails/19.jpg)
Dislocation picture,Cottrell cloud
D. Blavette, E. Cadel, A. Fraczkiewicz and A. Menand. Three-dimensional atomic-scale imaging of impurity segregationto line-defects. Science. Dec 17 (1999) pp. 2317-2319.
GPM UMR 6634 CNRS, Université de Rouen
Three-diensional atom-probe field-ion microscopy
Boron Al-Fe alloy
![Page 20: X-ray scattering in disordered structures and imperfects crystals Sylvain Ravy Laboratoire de physique des solides bât. 510, Université Paris-sud 91405,](https://reader036.fdocuments.net/reader036/viewer/2022070309/551d9d84497959293b8bfe88/html5/thumbnails/20.jpg)
Structure de l’eau liquide
Glace Ih (P63/mmc)(Glace de Bernal-Fowler)
Trétraèdre d’oxygène
26 MPa
209 MPa
400 MPa
Basse densité = 0.0295 mol.A-1
Haute densité = 0.0402 mol.A-1
Extrapolation
Extrapolation
Fonctions de corrélation O-O
E.D. Isaacs et al., Phys. Rev. Lett. 82 (1999) 600
A. Soper et al., Phys. Rev. Lett. 84 (2000) 2881
Rupture des liaisons H
![Page 21: X-ray scattering in disordered structures and imperfects crystals Sylvain Ravy Laboratoire de physique des solides bât. 510, Université Paris-sud 91405,](https://reader036.fdocuments.net/reader036/viewer/2022070309/551d9d84497959293b8bfe88/html5/thumbnails/21.jpg)
Transition liquide isotrope-nématique
B
Cliché de RX du 50.4 a) T>Tc b) T<Tc
a) b)
![Page 22: X-ray scattering in disordered structures and imperfects crystals Sylvain Ravy Laboratoire de physique des solides bât. 510, Université Paris-sud 91405,](https://reader036.fdocuments.net/reader036/viewer/2022070309/551d9d84497959293b8bfe88/html5/thumbnails/22.jpg)
Comparaison smectique-lamellaire
Phase lamellaire (DACl/H2O) :
Smectique A (8OCB) :
Cliché RX : 3h
B
B
Cliché RX :10h