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91.
92.
Yevgeni S. Mamasakhlisov Ali Naji Rudolf Podgornik 《Journal of statistical physics》2008,133(4):659-681
Charged systems with partially annealed charge disorder are investigated using field-theoretic and replica methods. Charge
disorder is assumed to be confined to macroion surfaces surrounded by a cloud of mobile neutralizing counterions in an aqueous
solvent. A general formalism is developed by assuming that the disorder is partially annealed (with purely annealed and purely
quenched disorder included as special cases), i.e., we assume in general that the disorder undergoes a slow dynamics relative to fast-relaxing counterions making it possible
thus to study the stationary-state properties of the system using methods similar to those available in equilibrium statistical
mechanics. By focusing on the specific case of two planar surfaces of equal mean surface charge and disorder variance, it
is shown that partial annealing of the quenched disorder leads to renormalization of the mean surface charge density and thus
a reduction of the inter-plate repulsion on the mean-field or weak-coupling level. In the strong-coupling limit, charge disorder
induces a long-range attraction resulting in a continuous disorder-driven collapse transition for the two surfaces as the
disorder variance exceeds a threshold value. Disorder annealing further enhances the attraction and, in the limit of low screening,
leads to a global attractive instability in the system. 相似文献
93.
对长程幂律关联能量序列进行了修正,使其能体现出无序度在一维长程关联无序系统中的影响,并利用重正化群方法,计算了能反映该系统局域化-退局域化转变的Lyapunov指数.结果表明,在由于关联指数p的影响而在系统中出现的局域化向退局域化的转变中,无序度起着相反的作用.当关联指数p一定而无序度W增大时,系统中心能区范围内由于长程关联而引起的扩展态逐渐向局域态转变.当无序度W增大到某一临界值Wc时,系统中所有本征态均转变为局
关键词:
长程关联
Lyapunov指数
无序度
局域化-退局域化转变 相似文献
94.
95.
Nir Tessler 《Journal of Polymer Science.Polymer Physics》2014,52(17):1119-1152
This review, which has a very deep tutorial nature to it, aims to collect a range of experimental techniques that are relevant to charge transport and place them all under one device‐physics framework. The types of semiconductors in mind are low mobility ones with an emphasis toward organic semiconductors. As this contribution needs to have a finite length, there are many important methods or techniques not covered in this review. My hope is that by covering methods that are very different in nature, it would make it easier to extend the understanding or intuition collected through this review to methods/techniques not mentioned. © 2014 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2014 , 52, 1119–1152 相似文献
96.
The structure of [(CH3)3NH]2Sb3Cl11 (space group P21/n; a = 10.374(2), b = 23.723(5), c = 11.884(2) Å, = 113.46(3)°; V = 2682.9(9) Å3) consists of a structurally novel [Sb3Cl2–
11] anion and two crystallographically nonequivalent trimethylammonium cations. The anion is composed of three deformed octahedra in the asymmetric part of the unit cell. The octahedra are connected with each other by edges and corners forming a characteristic polyanionic layer. Trimethylammonium cations, one ordered and one disordered, are connected to the inorganic sublattice by N—H···Cl hydrogen bonds. 相似文献
97.
98.
《Acta Crystallographica. Section C, Structural Chemistry》2018,74(10):1094-1104
Structures are reported for eight Schiff bases derived from various salicylaldehydes: five are newly synthesized and re‐investigations are reported for three previously reported structures, leading, in each case, to some revision of previous conclusions. In (E)‐N‐(3,4‐dimethylisoxazol‐5‐yl)‐4‐[(2‐hydroxybenzylidene)amino]benzenesulfonamide, C18H17N3O4S, (I), and (E)‐4‐[(5‐bromo‐2‐hydroxy‐3‐methoxybenzylidene)amino]‐N‐(3,4‐dimethylisoxazol‐5‐yl)benzenesulfonamide. C19H18BrN3O5S, (II), the isoxazole rings adopt different orientations relative to the rest of the molecules, despite the additional substituents in (II) being in the aryl ring remote from the isoxazole unit. The molecules of both (E)‐4‐bromo‐2‐[(2‐hydroxyphenylimino)methyl]‐6‐methoxyphenol, C14H12BrNO3, (III), and (E)‐4‐bromo‐2‐methoxy‐6‐[(2‐methoxyphenylimino)methyl]phenol, C15H14BrNO3, (IV), are both effectively planar; while (III) adopts the phenol–imine constitution, (IV) adopts the keto–amine constitution. (E)‐2‐Methoxy‐6‐[(2‐methoxyphenylimino)methyl]phenol, C15H15NO3, (V), which was determined previously using powder X‐ray data assuming the phenol–imine constitution, has now been refined from single‐crystal X‐ray data, confirming the phenol–imine constitution. In (E)‐3‐benzoyl‐2‐[(5‐fluoro‐2‐hydroxybenzylidene)amino]‐4,5,6,7‐tetrahydrobenzo[b]thiophene, C22H18FNO2S, (VI), the fused carbocyclic ring exhibits conformational disorder; both disorder components, having populations of 0.705 (4) and 0.295 (4), adopt half‐chair conformations. The isostructural (E)‐3‐benzoyl‐2‐[(2‐hydroxybenzylidene)amino)]‐4,5,6,7‐tetrahydrobenzo[b]thiophene, C22H19NO2S, (VII), which was originally reported as having a fully ordered structure [Kaur et al. (2014). Acta Cryst. E 70 , o476–o477], has been rerefined using the original data set and found to exhibit the same type of disorder as found in (VI), with disordered populations having occupancies of 0.851 (3) and 0.149 (3). The triclinic polymorph of (E)‐[(2‐hydroxyphenylimino)methyl]phenol, C13H11NO2, (VIII), which crystallizes with Z′ = 2 in the space group P, has been described variously as occurring as the keto–amine tautomer [Maciejewska et al. (1999). J. Phys. Org. Chem. 12 , 875–880] and as the phenol–imine tautomer [Tunç et al. (2009). J. Chem. Crystallogr. 39 , 672–676]. Rerefinement of this structure using one of the original data sets shows that both of the independent molecules exist in the keto–amine form. In the structures of compounds (I), (VI), (VII) and (VIII), hydrogen bonds generate simple chains, while a chain of rings is formed in (V). Sheets are formed by hydrogen bonds in both (II) and (III), while in (IV), the sheet structure is built from aromatic π–π stacking interactions. 相似文献
99.
《Acta Crystallographica. Section C, Structural Chemistry》2018,74(9):1058-1067
A global glide disorder has been discovered during an X‐ray investigation of the crystal structure of (Z)‐2‐[(E)‐(4‐methoxybenzylidene)hydrazinylidene]‐1,2‐diphenylethanone ( MHDE , C22H18N2O2) at room temperature. In another crystal, however, such disorder disappears (still at room temperature). Even though the disorder may be partly due to the poor quality of the harvested crystal, the structure can shed light on the nature of disorder. With the help of quantum chemical calculations, it is found that the global disorder seems to be connected with the need for stabilization of the somewhat rigid but mobile and unstable molecular structure. The most relevant feature driving the packing of the disordered structure concerns the slight perturbations (such as glide) of two or more disorder components (fractional occupancies) distributed throughout the crystal. 相似文献
100.
The solid-state structure of the triple-decker salt [Cp*Fe(-5:5-C4Me4P)RuCp*] · CF3SO3 shows orientational disorder for the pseudosymmetric cations. A chemically related compound was used to define a restrained structure model. Comparison of different refinement strategies proves that this restrained model is superior to an unrestrained treatment. 相似文献