Epitaxial growth of crystals

In 1985 Car and Parrinello invented a method [111-113] in which molecular dynamics (MD) methods are combined with first-principles computations such that the interatomic forces due to the electronic degrees of freedom are computed by density functional theory [114-116] and the statistical properties by the MD method. This method and related ab initio simulations have been successfully applied to carbon [117], silicon [118-120], copper [121], surface reconstruction [122-128], atomic clusters [129-133], molecular crystals [134], the epitaxial growth of metals [135-140], and many other systems for a review see Ref. 113. 

Supramolecular structures formed during the crystallization of the melt under a tensile stress have already been described by Keller and Machin25. These authors have proposed a model for the formation of structures of the shish-kebab type according to which crystallization occurs in two stages in the first stage, the application of tensile stress leads to the extension of the molecules and the formation of a nucleus from ECC and the second stage involves epitaxial growth of folded-chain lamellae. 

Thin polymer films may also be investigated by TEM and high resolution images are obtained for e.g. thin films of liquid crystalline polymers [64]. Usually thin microtome cuts from bulk samples are investigated, but also epitaxial growth of polyoxymethylene on NaCl [152], chain folding of polyethylene crystals [153], epitaxial crystallization of polypropylene on polystyrene [154] or monomolecular polystyrene particles [155] are observed. The resolution is, however, in most cases not comparable to STM. 

MBE (molecular beam epitaxy), which involves epitaxial growth of thin films on either the same material as substrate (homoepitaxial) or a lattice-matched substrate (heteroepitaxial) the heated substrate reacts with a molecular beam of compounds containing the constituent elements of the semiconductor as well as any dopants the resultant film is essentially a single crystal slow growth rates produce films from a few nanometers thick to at most several hundred nanometers that have very high purity and controlled levels of dopants. 

Zhang, W.P. and Dorset, D.L. (1990). Epitaxial growth and crystal structure analysis of perfluorotetracosane Macromolecules, 23, 4322-4326. 

The mechanism by which hematite is formed from ferrihydrite in an aqueous system, appears more complicated than that by which goethite forms. If hematite crystals are added to the system they do not function as seeds for hematite formation but induce epitaxial growth of goethite instead (Atkinson et al. 1968 Cornell Giovanoli, 1985). 

Epitaxial growth of overlayer on the plane is envisaged in the field of material physics. Epitaxy of a relatively thick layer measurable In microns Is explained primarily by the matching of crystal planes. We assume a similar epitaxy for the deposition of silica on the external surface of zeolites, although direct observation by electron microscopy is extremely difficult. 

Suntola T (1994) Atomic Layer Epitaxy (Handbook of Crystal Growth) Elsevier Science BV, Amsterdam... 

Uyeda s group investigated by electron microscopy and diffraction (75) the epitaxial growth of amino acids on the (001) plane of nickel film or on the one modified with amino acid at a specific pH and temperature. The most preferable positions for the mutual orientation of both crystals, nickel... 

Monolayer structures and epitaxial growth of vapor-deposited crystalline phthalocyanine films on single crystal copper substrates were studied using low energy electron diffraction Ordered monolayers of three different phthalocyanines, copper, iron, and metal-free, were seen on two different faces of copper, the (111) and (100). The monolayer structures formed were different on the two crystal faces and the several phthalocyanines yield nonidentical monolayer structures. 

The use of surface analytical techniques in the study of epitaxial growth of Si has been primarily restricted to studies of the factors which affect the growth of a single crystalline layer substrate cleaning, contamination and crystal quality. 

Hoogenboom JP, van Langen-Suurling AK, Romijn J, van Blaaderen A (2004) Epitaxial growth of a colloidal hard-sphere hep crystal and the effects of epitaxial mismatch on crystal structure. Phys Rev E 69 051602-051617... 

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