![]() ![]() The book brings the reader through the entire development of the proof of this result. Heuristically, the main result can be stated this way: a droplet of one phase immersed in the opposite one will be formed with the separation line following with high accuracy the shape yielded by the Wulff construction. Its value is chosen to lie in the interval between the spontaneous magnetizations of pure phases. Namely, the authors investigate the phenomenon of phase separation in a (small) canonical ensemble characterized by a fixed total spin in a finite volume. This research monograph considers the Wulff construction in the case of a two-dimensional Ising ferromagnet with periodic boundary conditions and at sufficiently low temperatures. Assuming that the anisotropic interfacial free energy (depending on the orientation of the interface with respect to the crystal axes) is known, the Wulff construction yields the shape of crystal in equilibrium and allows one to understand its main features. The Wulff shape is the shape that possesses the lowest surface energy for a fixed volume, and hence represents the ideal shape that the crystal would take in the absence of other constraints. Theoretical calculations confirm the rationality of the experimental scheme and elucidate the underlying reason for the fungistatic and fungicidal activity against Candida albicans.A theory of the equilibrium shape of crystal assuming minimal surface free energy was formulated at the beginning of the century by Wulff. Wulffman is a program for interactively examining the Wulff shapes of crystals with specified symmetries. A correlation between the exposed surfaces and antifungal activity was revealed, and an explanation to this behavior that arises from different morphologies and structural data was provided. PARTICLE SIZE EFFECTS ON WULFF CONSTRUCTIONS 358 SurfaceS ience 150(1985) 358-366worth-Holland,Amsterdam PARTICLE SIZE EFFECTS ON WULFF CONSTRUCTIONS L.D.MARKS Received 11July 1984 acceptedforpublication16October 1984 Theequilibriumstrctureof small particles isanalysed byminimisingthetotal surface enrgyofatomisticclusters. A large decrease in surface energy for the (111) surface provided the experimental morphology for crystals synthesized using water and ethanol as solvents when the surface energies for both (011) and (001) surfaces increased, the crystal morphology obtained using ammonia as a solvent was reproduced. The experimental morphology was obtained by varying the surface energy ratio for each facet. The (011) orientation was the predominant surface in the morphology. The thermodynamic equilibrium shape of the β-Ag2MoO4 crystals was determined based on the surface energies calculated using Wulff construction. MARKS Received 11 July 1984 accepted for publication 16 October 1984 The equilibrium structure of small particles is analysed by minimising the total surface energy of atomistic clusters. The optical properties were investigated by UV-Vis spectroscopy and photoluminescence measurements at room temperature. 358 Surface Science 150 (1985) 358-366 worth-Holland, Amsterdam PARTICLE SIZE EFFECTS ON WULFF CONSTRUCTIONS L.D. The samples were characterized by X-ray diffraction, micro-Raman spectroscopy, field emission scanning electron microscopy, and transmission electron microscopy with energy dispersive spectroscopy. Assuming that the anisotropic interfacial free energy (depending on the orientation of the interface with respect to the crystal axes) is known, the Wulff construction yields the shape of crystal in equilibrium and allows one to understand its main features. Wulffman is a program for interactively examining the Wulff shapes of crystals with specified symmetries. In this construction, the distance of a facet from the crystal center is proportional to the surface. β-Ag2MoO4 samples were prepared by a co-precipitation method using different solvents (water, ethanol and ammonia), and their antifungal activity against Candida albicans was investigated. The Wulff construction gives the crystal shape under equilibrium conditions 19, 57, 58. In this case a cubic crystal is required, and FCC is probably the only crystal structure that makes physical sense. In this study, we investigate the structure, antifungal activity, and optical properties of β-Ag2MoO4 using experimental and theoretical approaches. Wulff construction of twinned particles WulffPack can also construct decahedral and icosahedral particles using the so-called modified Wulff construction Mar83. ![]()
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