Pub Date : 1990-12-01DOI: 10.1051/JPHYS:0199000510230267300
P. Meakin, R. Jullien
Random packings of identical spheres of unit diameter were built according to a procedure in which spheres are released one after another along randomly positionned vertical trajectories and then follow the path of steepest descent on the others until they reach a stable position under gravity. Once a packing has been built, smaller spheres, of diameter d does not diverge but saturates to c 11 and the histogram N reaches an exponential shape whose large ΔZ tail is well fitted by N α exp(−0.103 ΔZ). It is shown that such behavior is due to a non zero proportion of equilateral triangles of tangent spheres in the random packing
{"title":"Simulation of small particle penetration in a random medium","authors":"P. Meakin, R. Jullien","doi":"10.1051/JPHYS:0199000510230267300","DOIUrl":"https://doi.org/10.1051/JPHYS:0199000510230267300","url":null,"abstract":"Random packings of identical spheres of unit diameter were built according to a procedure in which spheres are released one after another along randomly positionned vertical trajectories and then follow the path of steepest descent on the others until they reach a stable position under gravity. Once a packing has been built, smaller spheres, of diameter d does not diverge but saturates to c 11 and the histogram N reaches an exponential shape whose large ΔZ tail is well fitted by N α exp(−0.103 ΔZ). It is shown that such behavior is due to a non zero proportion of equilateral triangles of tangent spheres in the random packing","PeriodicalId":14747,"journal":{"name":"Journal De Physique","volume":"54 1","pages":"2673-2680"},"PeriodicalIF":0.0,"publicationDate":"1990-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84494335","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1990-12-01DOI: 10.1051/JPHYS:0199000510230265300
F. F. Abraham, D. Nelson
Fluctuations in polymerized membranes are explored via extensive molecular dynamics simulations of simplified «tethered surface» models. The entropic rigidity associated with repulsive second-nearest-neighbor interactions leads to a flattening of «phantom surfaces». An attractive interaction in the presence of distant self-avoidance leads to a collapsed membrane with fractal dimension three at sufficiently low temperatures. When the attractive interaction is turned off, the surface returns to the flat phase found in earlier simulations. A study of density profiles and hexatic internal order allows a simple physical interpretation of results for the structure function of oriented membranes
{"title":"Fluctuations in the flat and collapsed phases of polymerized membranes","authors":"F. F. Abraham, D. Nelson","doi":"10.1051/JPHYS:0199000510230265300","DOIUrl":"https://doi.org/10.1051/JPHYS:0199000510230265300","url":null,"abstract":"Fluctuations in polymerized membranes are explored via extensive molecular dynamics simulations of simplified «tethered surface» models. The entropic rigidity associated with repulsive second-nearest-neighbor interactions leads to a flattening of «phantom surfaces». An attractive interaction in the presence of distant self-avoidance leads to a collapsed membrane with fractal dimension three at sufficiently low temperatures. When the attractive interaction is turned off, the surface returns to the flat phase found in earlier simulations. A study of density profiles and hexatic internal order allows a simple physical interpretation of results for the structure function of oriented membranes","PeriodicalId":14747,"journal":{"name":"Journal De Physique","volume":"1947 1","pages":"2653-2672"},"PeriodicalIF":0.0,"publicationDate":"1990-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"91205168","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1990-12-01DOI: 10.1051/JPHYS:0199000510240281300
P. Tong, T. Witten, J. Huang, L. Fetters
Etude par diffusion optique aux petits angles de l'interaction entre un colloide stabilise par un agent de surface et le polyisoprene hydrogene. A l'aide d'un developpement du viriel, l'intensite de diffusion est calculee en fonction des concentrations en polymere et en colloide; la formule obtenue permet de mesurer le volume exclu mutuel entre le polymere et le colloide; le deuxieme coefficient du viriel des particules colloidales dans la solution diluee de polymere est aussi deduit. Cette methode d'obtention des parametres d'interaction dans un melange polymere-colloide est capable de sonder les changements du potentiel d'interaction de la suspension colloidale dus a l'addition du polymere (effet de depletion)
{"title":"Interactions in mixtures of colloid and polymer","authors":"P. Tong, T. Witten, J. Huang, L. Fetters","doi":"10.1051/JPHYS:0199000510240281300","DOIUrl":"https://doi.org/10.1051/JPHYS:0199000510240281300","url":null,"abstract":"Etude par diffusion optique aux petits angles de l'interaction entre un colloide stabilise par un agent de surface et le polyisoprene hydrogene. A l'aide d'un developpement du viriel, l'intensite de diffusion est calculee en fonction des concentrations en polymere et en colloide; la formule obtenue permet de mesurer le volume exclu mutuel entre le polymere et le colloide; le deuxieme coefficient du viriel des particules colloidales dans la solution diluee de polymere est aussi deduit. Cette methode d'obtention des parametres d'interaction dans un melange polymere-colloide est capable de sonder les changements du potentiel d'interaction de la suspension colloidale dus a l'addition du polymere (effet de depletion)","PeriodicalId":14747,"journal":{"name":"Journal De Physique","volume":"10 1","pages":"2813-2827"},"PeriodicalIF":0.0,"publicationDate":"1990-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85416834","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1990-12-01DOI: 10.1051/JPHYS:0199000510240273900
A. Deville, B. Gaillard
An ESR signal detected in a Bi compound has recently been attributed to the SC phase, arguing that two criteria (value and thermal behaviour of the intensity) were met. We draw attention to the weakness of this argument, recalling a canonical example Un signal RPE observe dans un compose au bismuth a ete recemment attribue a la phase SC, en s'appuyant sur le fait que deux criteres (valeur et comportement thermique de l'intensite) sont verifies. Nous attirons l'attention sur la faiblesse de cette argumentation, et rappelons un exemple canonique
在Bi化合物中检测到的ESR信号最近被归因于SC相，认为满足两个标准(强度的值和热行为)。我们提请注意这一论点的弱点，回顾一个典型的例子，即非信号RPE观测数据不包含一个相位SC的初始值和初始值属性，即使其“适应性sur le fait que deux criteres”(值与分量热特性)也不验证。我们的注意力集中在我们的论证中，而不是在我们的论证中
{"title":"A comment upon the use of two criteria in the identification of intrinsic esr in high Tc oxides","authors":"A. Deville, B. Gaillard","doi":"10.1051/JPHYS:0199000510240273900","DOIUrl":"https://doi.org/10.1051/JPHYS:0199000510240273900","url":null,"abstract":"An ESR signal detected in a Bi compound has recently been attributed to the SC phase, arguing that two criteria (value and thermal behaviour of the intensity) were met. We draw attention to the weakness of this argument, recalling a canonical example Un signal RPE observe dans un compose au bismuth a ete recemment attribue a la phase SC, en s'appuyant sur le fait que deux criteres (valeur et comportement thermique de l'intensite) sont verifies. Nous attirons l'attention sur la faiblesse de cette argumentation, et rappelons un exemple canonique","PeriodicalId":14747,"journal":{"name":"Journal De Physique","volume":"33 1","pages":"2739-2741"},"PeriodicalIF":0.0,"publicationDate":"1990-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76196748","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1990-12-01DOI: 10.1051/JPHYS:0199000510230268900
C. Lac, J. Ball, J. Bystrický, J. Derégel, F. Lehár, A. Lesquen, L. Rossum, J. Fontaine, F. Perrot, P. Winternitz
The direct reconstruction of the elastic scattering amplitudes at eleven energies between 0.83 and 2.7 GeV is described. Complete sets of spin dependent observables used for this reconstruction were measured in the nucleon-nucleon experimental program at Saturne II. The invariant amplitudes a, b, c, d and e were deduced using the least square method fit to the experimental data. A search for solutions starting from random initial values was performed to determine different possible sets of amplitudes. The absolute values show a similar angular dependence at all energies and for all solutions. The dependence of phases show discrete ambiguities especially at the higher energies. One of the solutions at 2.1 GeV suggests a behaviour which could be related to a dibaryon resonance of mass 2.73 GeV with the half-width at the half-maximum less than 50 MeV.
{"title":"Direct reconstruction of pp elastic scattering amplitudes from experimental data between 0.83 and 2.7 GeV","authors":"C. Lac, J. Ball, J. Bystrický, J. Derégel, F. Lehár, A. Lesquen, L. Rossum, J. Fontaine, F. Perrot, P. Winternitz","doi":"10.1051/JPHYS:0199000510230268900","DOIUrl":"https://doi.org/10.1051/JPHYS:0199000510230268900","url":null,"abstract":"The direct reconstruction of the elastic scattering amplitudes at eleven energies between 0.83 and 2.7 GeV is described. Complete sets of spin dependent observables used for this reconstruction were measured in the nucleon-nucleon experimental program at Saturne II. The invariant amplitudes a, b, c, d and e were deduced using the least square method fit to the experimental data. A search for solutions starting from random initial values was performed to determine different possible sets of amplitudes. The absolute values show a similar angular dependence at all energies and for all solutions. The dependence of phases show discrete ambiguities especially at the higher energies. One of the solutions at 2.1 GeV suggests a behaviour which could be related to a dibaryon resonance of mass 2.73 GeV with the half-width at the half-maximum less than 50 MeV.","PeriodicalId":14747,"journal":{"name":"Journal De Physique","volume":"175 4","pages":"2689-2716"},"PeriodicalIF":0.0,"publicationDate":"1990-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"72569838","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1990-11-01DOI: 10.1051/JPHYS:0199000510210247700
F. Argoul, A. Arneodo
We report an experimental study of the statics and dynamics of electrodeposition of zinc in an aqueous medium, in the intermediate regime between dendritic and DLA-like metallic clusters. During the growth process, periodic and nonperiodic oscillations of the voltage are recorded under constant applied current intensity. Period-doubling bifurcations are identified. Analysis of the data in terms of phase portraits, Poincare maps and 1-D maps shows that the fractal geometry of these electrochemical deposits is the signature of a low-dimensional deterministic chaotic dynamics which displays sensitivity to initial conditions. The study of the apparently more complex dynamics recorded in the DLA limit is a very promising experimental challenge Nous presentons ici les resultats d'une etude experimentale du processus d'electrodeposition de zinc en milieu aqueux bidimensionnel. Les regimes etudies sont intermediaires entre des croissances metalliques de nature dendritique et des croissances plus desordonnees similaires aux agregats fractals engendres par simulation numerique de modele d'agregation limitee par la diffusion de Witten et Sander (DLA model). L'etude de ces dynamiques complexes apporte une premiere evidence experimentale du caractere chaotique deterministe de ces phenomenes de structuration d'interface et la signature d'une dynamique a faible nombre de degres de liberte. L'etude dynamique de regimes encore plus complexes observes dans la limite DLA s'avere etre un challenge experimental des plus prometteurs
{"title":"Experimental evidence for deterministic chaos in electrochemical deposition","authors":"F. Argoul, A. Arneodo","doi":"10.1051/JPHYS:0199000510210247700","DOIUrl":"https://doi.org/10.1051/JPHYS:0199000510210247700","url":null,"abstract":"We report an experimental study of the statics and dynamics of electrodeposition of zinc in an aqueous medium, in the intermediate regime between dendritic and DLA-like metallic clusters. During the growth process, periodic and nonperiodic oscillations of the voltage are recorded under constant applied current intensity. Period-doubling bifurcations are identified. Analysis of the data in terms of phase portraits, Poincare maps and 1-D maps shows that the fractal geometry of these electrochemical deposits is the signature of a low-dimensional deterministic chaotic dynamics which displays sensitivity to initial conditions. The study of the apparently more complex dynamics recorded in the DLA limit is a very promising experimental challenge Nous presentons ici les resultats d'une etude experimentale du processus d'electrodeposition de zinc en milieu aqueux bidimensionnel. Les regimes etudies sont intermediaires entre des croissances metalliques de nature dendritique et des croissances plus desordonnees similaires aux agregats fractals engendres par simulation numerique de modele d'agregation limitee par la diffusion de Witten et Sander (DLA model). L'etude de ces dynamiques complexes apporte une premiere evidence experimentale du caractere chaotique deterministe de ces phenomenes de structuration d'interface et la signature d'une dynamique a faible nombre de degres de liberte. L'etude dynamique de regimes encore plus complexes observes dans la limite DLA s'avere etre un challenge experimental des plus prometteurs","PeriodicalId":14747,"journal":{"name":"Journal De Physique","volume":"1 1","pages":"2477-2487"},"PeriodicalIF":0.0,"publicationDate":"1990-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88887030","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1990-11-01DOI: 10.1051/JPHYS:0199000510220259500
F. Lequeux, R. Hocquart
A model of coupling between a mouse drain and a nematic order parameter is developed. The geometry of the chain for each mode, in simple shear flow is calculated. The local torque and normal stress sign are discussed. This implies non trivial ways to introduce the opposite coupling (from chain to parameter order) in order to get a model for mouse nematic polymers
{"title":"Rheological Rouse model for a polymer in a nematic matrix","authors":"F. Lequeux, R. Hocquart","doi":"10.1051/JPHYS:0199000510220259500","DOIUrl":"https://doi.org/10.1051/JPHYS:0199000510220259500","url":null,"abstract":"A model of coupling between a mouse drain and a nematic order parameter is developed. The geometry of the chain for each mode, in simple shear flow is calculated. The local torque and normal stress sign are discussed. This implies non trivial ways to introduce the opposite coupling (from chain to parameter order) in order to get a model for mouse nematic polymers","PeriodicalId":14747,"journal":{"name":"Journal De Physique","volume":"83 1","pages":"2595-2604"},"PeriodicalIF":0.0,"publicationDate":"1990-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80691177","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1990-11-01DOI: 10.1051/JPHYS:0199000510210246500
A. Vainrub, E. Canadell, D. Jérome, P. Bernier, T. Nunes, M. Bruniquel, P. Cassoux
High resolution 13 C NMR results for the organic conductor TTF[Ni(dmit) 2 ] 2 enriched by 13 C isotope in Ni(dmit) 2 molecules are reported. Variable temperature magic angle spinning experiments were performed between 160 and 295 K. Paramagnetic Knight shifts in the range 41-106.5 ppm at room temperature are observed for all Ni(dmit) 2 carbon sites. These shifts are slightly temperature dependent for inner carbons. However, for outer carbons, the shifts strongly decrease towards low temperature due to precursor effects of the charge density wave (CDW) transition. The results confirm the occurrence of both HOMO (highest occupied molecular orbital) and LUMO (lowest unoccupied molecular orbital) conduction bands and are compared with calculated partial contributions of individual carbon atoms to the density of states at the Fermi level. We suggest that CDW effects above 160 K are associated with the LUMO bands
{"title":"Temperature dependent locally resolved 13C knight shifts in the organic conductor TTF[Ni(dmit)2]2","authors":"A. Vainrub, E. Canadell, D. Jérome, P. Bernier, T. Nunes, M. Bruniquel, P. Cassoux","doi":"10.1051/JPHYS:0199000510210246500","DOIUrl":"https://doi.org/10.1051/JPHYS:0199000510210246500","url":null,"abstract":"High resolution 13 C NMR results for the organic conductor TTF[Ni(dmit) 2 ] 2 enriched by 13 C isotope in Ni(dmit) 2 molecules are reported. Variable temperature magic angle spinning experiments were performed between 160 and 295 K. Paramagnetic Knight shifts in the range 41-106.5 ppm at room temperature are observed for all Ni(dmit) 2 carbon sites. These shifts are slightly temperature dependent for inner carbons. However, for outer carbons, the shifts strongly decrease towards low temperature due to precursor effects of the charge density wave (CDW) transition. The results confirm the occurrence of both HOMO (highest occupied molecular orbital) and LUMO (lowest unoccupied molecular orbital) conduction bands and are compared with calculated partial contributions of individual carbon atoms to the density of states at the Fermi level. We suggest that CDW effects above 160 K are associated with the LUMO bands","PeriodicalId":14747,"journal":{"name":"Journal De Physique","volume":"16 1","pages":"2465-2476"},"PeriodicalIF":0.0,"publicationDate":"1990-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81567099","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1990-11-01DOI: 10.1051/JPHYS:0199000510210248900
C. Craven, G. Dosseh, B. Rousseau, A. Fuchs
The phenomenon of premelting has been investigated by proton n.m.r. in polycrystalline benzene of various purity. Our results suggest that premelting initiates at grain boundaries. The exact nature of the molten domains near the standard melting point is not yet clear but is presumably analogous to what is obtained in the surface melting experiments, i.e. a «strongly correlated interface liquid» Le phenomene de prefusion dans le benzene polycristallin de purete variable a ete etudie par r.m.n. du proton. Nos resultats suggerent que la prefusion debute aux joints de grains. La nature exacte des domaines fondus n'est pas encore tres claire mais il semble que l'on observe un liquide d'interface tres correle, comme les auteurs qui etudient la fusion de surface
{"title":"Grain boundary premelting in crystalline benzene as studied by proton N.M.R.","authors":"C. Craven, G. Dosseh, B. Rousseau, A. Fuchs","doi":"10.1051/JPHYS:0199000510210248900","DOIUrl":"https://doi.org/10.1051/JPHYS:0199000510210248900","url":null,"abstract":"The phenomenon of premelting has been investigated by proton n.m.r. in polycrystalline benzene of various purity. Our results suggest that premelting initiates at grain boundaries. The exact nature of the molten domains near the standard melting point is not yet clear but is presumably analogous to what is obtained in the surface melting experiments, i.e. a «strongly correlated interface liquid» Le phenomene de prefusion dans le benzene polycristallin de purete variable a ete etudie par r.m.n. du proton. Nos resultats suggerent que la prefusion debute aux joints de grains. La nature exacte des domaines fondus n'est pas encore tres claire mais il semble que l'on observe un liquide d'interface tres correle, comme les auteurs qui etudient la fusion de surface","PeriodicalId":14747,"journal":{"name":"Journal De Physique","volume":"26 1","pages":"2489-2499"},"PeriodicalIF":0.0,"publicationDate":"1990-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82849060","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1990-11-01DOI: 10.1051/JPHYS:0199000510210243100
M. Kleman
The phase degrees of freedom of aperiodic crystals (quasicrystals) are far from being understood. In this paper we study in great detail the geometrical and topological properties of the «phase space» of quasicrystals, for usual quasicrystalline symmetries (icosahedral and pentagonal cases) and for the cases d=3, d ∥ =1 and d=4, d ∥ =2. It is shown that the universal covering of the phase space is a curved crystal of negative Gaussian curvature, whose group of automorphisms contains therefore the fundamental group of the phase space as a subgroup. This fundamental group is calculated in each case. The results do not depend in any way on the cho Les degres de liberte relatifs a la phase des cristaux aperiodiques sont loin d'etre compris. Dans cet article, nous etudions en grand detail les proprietes geometriques et topologiques de l'espace representatif de la phase pour des symetries quasicristallines usuelles (icosaedrique et pentagonale) et pour les cas d=3, d ∥ =1 et d=4, d∥=2. On montre que l'espace de la phase a pour revetement universel un cristal d'espace courbe de courbure gaussienne negative; le groupe fondamental de l'espace de la phase est un sous-groupe du groupe d'automorphismes de ce cristal courbe. Nous le calculons dans chaque cas envisage. Les resultats ne dependent en aucune maniere du choix et de la «surface atomique» (le motif) qui decore la cellule de base du cristal hypercubique d'ou le quasicristal est engendre. En consequence, ils ne dependent pas non plus du fait que les phasons sont continus ou discrets. Ces recherches constituent un premier pas necessaire dans l'etude de la nature geometrique et topologique des deformations du type «phason». On discute en outre de l'homomorphisme entre l'espace de la phase et le groupe qui classe les dislocations. Finalement nous indiquons sans entrer dans les details que le groupe fondamental de l'espace de la phase classe les defauts topologiques du type phason
非周期晶体(准晶体)的相自由度尚不清楚。在本文中，我们详细地研究了准晶体的“相空间”的几何和拓扑性质，对于通常的准晶体对称(二十面体和五边形的情况)，对于d=3, d∥=1和d=4, d∥=2的情况。证明了相空间的普遍覆盖是一个负高斯曲率的弯曲晶体，因此其自同构群包含相空间的基群作为子群。这个基本组是在每种情况下计算出来的。结果不以任何方式依赖于三个自由度的关系，一个阶段的非周期性特征，一个阶段的非周期性特征。在第二篇文章中，noous etututions en grand detail les proprietes geometriques et topologiques de l'空间表征de la phase pour des des systemes准晶uselles (icosaedrique et pentagonale) et pour les cas d=3, d∥= 1 et d=4, d∥=2。On montre que l'espace de la phase a pour reveement universsel uncristle d'espace courbe de courbure gaussienne negative;基本群是指相空间的基本群;自同构群是指晶体的自同构群。现在，我们的计算和我们的设想是一样的。这些结果依赖于“表面原子”、“表面原子”、“细胞”、“晶体基”、“超立方体”和“准晶体”。因此，我们需要依赖于非事实和非事实，而不是连续的离散相。他的研究主要是关于“相位”型变形的组成、几何和拓扑结构的性质和必要性。讨论了位错的同态中心、位错的空间、位错的群、位错的类。finfinement的用法和样例:finfinement的用法和样例:finfinement的用法和样例:finfinement的用法和样例:finfinement
{"title":"Topology of the phase in aperiodic crystals","authors":"M. Kleman","doi":"10.1051/JPHYS:0199000510210243100","DOIUrl":"https://doi.org/10.1051/JPHYS:0199000510210243100","url":null,"abstract":"The phase degrees of freedom of aperiodic crystals (quasicrystals) are far from being understood. In this paper we study in great detail the geometrical and topological properties of the «phase space» of quasicrystals, for usual quasicrystalline symmetries (icosahedral and pentagonal cases) and for the cases d=3, d ∥ =1 and d=4, d ∥ =2. It is shown that the universal covering of the phase space is a curved crystal of negative Gaussian curvature, whose group of automorphisms contains therefore the fundamental group of the phase space as a subgroup. This fundamental group is calculated in each case. The results do not depend in any way on the cho Les degres de liberte relatifs a la phase des cristaux aperiodiques sont loin d'etre compris. Dans cet article, nous etudions en grand detail les proprietes geometriques et topologiques de l'espace representatif de la phase pour des symetries quasicristallines usuelles (icosaedrique et pentagonale) et pour les cas d=3, d ∥ =1 et d=4, d∥=2. On montre que l'espace de la phase a pour revetement universel un cristal d'espace courbe de courbure gaussienne negative; le groupe fondamental de l'espace de la phase est un sous-groupe du groupe d'automorphismes de ce cristal courbe. Nous le calculons dans chaque cas envisage. Les resultats ne dependent en aucune maniere du choix et de la «surface atomique» (le motif) qui decore la cellule de base du cristal hypercubique d'ou le quasicristal est engendre. En consequence, ils ne dependent pas non plus du fait que les phasons sont continus ou discrets. Ces recherches constituent un premier pas necessaire dans l'etude de la nature geometrique et topologique des deformations du type «phason». On discute en outre de l'homomorphisme entre l'espace de la phase et le groupe qui classe les dislocations. Finalement nous indiquons sans entrer dans les details que le groupe fondamental de l'espace de la phase classe les defauts topologiques du type phason","PeriodicalId":14747,"journal":{"name":"Journal De Physique","volume":"3 1","pages":"2431-2447"},"PeriodicalIF":0.0,"publicationDate":"1990-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74930706","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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