Crystal structure, thin films

Vop D, Kruger P, Mazur A and Pollmann J 1999 Atomic and electronic structure of WSe from ah initio theory bulk crystal and thin film systems Phys. Rev. B 60 14 311... 

A similar one-step process was employed successfully [66] to prepare well-crystallized CdS thin films of optical quality on Au(lll) from an aqueous solution of CdSOa, EDTA, and Na2S at room temperature. A phase transition from cubic (zinc blende) to hexagonal (wurtzite) CdS structure was observed with decreasing pH below 5, while highly preferential orientation along [11.0] directions for the... 

Starting with basic physical concepts and synthetic techniques, the book describes how molecules assemble into highly ordered structures as single crystals and thin films, with examples of characterization, morphology and properties. Special emphasis is placed on the importance of surfaces and interfaces. The final chapter gives a personal view on future possibilities in the field. 

Conjugated polymers and organic molecular crystals or thin films are extended systems whose electronic structure is beyond direct ab initio theory, although many valuable treatments of oligomers have been reported. Simple models are advanta-... 

As a probe of lattice vibrations, Raman spectroscopy is very sensitive to intrinsic crystal properties and extrinsic stimuli, especially in semiconductors. It may be employed to study crystal structure and quality, crystal orientation, optical interactions, chemical composition, phases, dopant concentration, surface and interface chemistry, and local temperatme or strain. As an optical technique, important sample information may be obtained rapidly and nondestructively with minimal sample preparation. Submicron lateral resolution is possible with the use of confo-cal lenses. These features have made it a vital tool for research labs studying semiconductor-based technologies. They also are increasingly important for the study of semiconductor NWs fabricated by both top-down and bottom-up approaches since many of the common characterization methods used with bulk crystals or thin films cannot be applied to NWs in a direct manner. 

The most basic photochromic systems are those that undergo a light-induced structural rearrangement. Isomerizations often involve large nuclear rearrangements which, for example, can change the symmetry or convert from a linear to bent structure. This property is especially useful for doping of liquid crystals and thin films, in which the microscopic structure of individual dopant molecules can be used to modulate the macroscopic properties of a host system. 

S. Schiefer, M. Huth, A. Dobrinevski, and B. Nickel, Determination of the Crystal Structure of Substrate-Induced Pentacene Polymorphs in Fiber Structured Thin Films, J. Am. Chem. Soc. 129, 10316-10317(2007). 

During the last two decades a number of surface science techniques were developed that provided atomic level information on atomic or electronic surface structure as well as surface composition with ever improving spatial and time resolution [1]. LEED, XPS, AES, and SIMS have been routinely applied for surface characterization of single-crystal or thin film model catalysts used in the course for catalytic reaction studies. However, their drawback has been the need for a high vacuum working environment. To overcome this restriction, UHV compatible high pressure cells were developed [2,3] that combined capabilities to perform catalytic... 

Composition, structure, synthesis, single crystal and thin film 18, 17.3.10.2.2 Ba2Fci2022Zn2 Ba2Zn2Fe,2022 Structure 6, 3.10.3.2.2.1... 

Composition, structure, synthesis, single crystal and thin film ... 

In this paper, we review the determination of the shape and the structure of metal particles by electron microscopy as illustrated by examples of Pd clusters epitaxially oriented on oxide single crystals and thin films of MgO and ZnO. The metal-oxide interfaces are characterized by HRTEM profile-view imaging, numerical analysis of the images, and image simulations by the multi-slice technique. 

In crystallization from the melt, polycrystalline regions sometimes occur which are called spherulites because of their spherical form and optical properties. Microtome sections show that their internal structure is radially symmetric. Circular structures of similar internal construction occur in the crystallization of thin films (Figure 5-23). They are therefore likewise termed spherulites, since they can be considered as cross sections of bulk-crystallized spherulites. 

When analyzing the achievements of synthetic chemists from the aspect of dimensionahty, it becomes clear that there is substantial room for development, notably in the direction of extended - yet controlled - 2-D and three-dimensional (3-D) structures (Figure 28.2). Although, of course, it has always been at the heart of chemistry to create extended organic matter in the bulk phase, crystals, and thin films, the tools available for this purpose were in the main noncovalent interactions and phase segregation. Clearly, the development of methods that would permit... 

In the early work of Rigby and Roe (370) it was shown that a imited atom model of PE would spontaneously pass from an isotropic to a nematic phase on lowering the temperature. More recently, the same model potential has been applied by Koyama and co-workers (460), who found a Tg at about 230 K, with significant ordering of the chains occurring between 300 and 330 K. The latter is taken to indicate incipient crystallization. The work on a polymer film by Ito and co-workers (340) used the same model, and found a crystalline structure below and at 300 K. Thus, if the simulation times are sufficiently long relative to the relaxation time of the modeled chains, it is possible to observe at least the onset of crystallization in a condensed phase. The timescale for crystallization in thin films may be shorter than in the bulk Ito and co-workers (340) have shown that their PE film forms... 

O Kane WJ, Young RJ, Ryan AJ (1995) The effect of annealing on the structure and properties of isotactic polypropylene films. J Macromol Sci Phys B34 427 Padden FJ, Keith HD (1966) Crystallization in thin films of isotactic polypropylene. J Appl Phys... 

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