The morphology of the reconstructed {001} surface of MgAl2O4 spinel is studied by scanning probe microscopy (SPM). The observations show that the {001} surface of MgAl2O4 may exist as two variants which are related through 90° rotation about the [001] axis. These surface variants exhibit different lateral forces and tend to grow/evaporate and to etch anisotropically along either the [110] or the [110] directions of the crystal. Surface terraces that are formed by different variants were found to be separated by ∼2.0 Å-high steps, while the terraces which belong to the same variant are separated by ∼4.0 Å-high steps. It is expected that the origins of the preferential motion of ledges on the {001} spinel surface is related to the anisotropic distribution of cations along either the [110] or the [110] directions within the {001} crystal planes in the spinel crystal.

Ecological situation of the last decades has driven an interest to the production of nutrients with natural food supplements. We have developed a number of cream-butter sorts containing vegetable additives, which are recommended as the dietary and prophylactic food supplements [1]. These kinds of butter exhibit unusual plasticity and enhanced durability, which are attributed to the features of their microstructure formation.

Atomistic simulation methods have been used to model the structure of the (1014) surfaces of calcite, dolomite, and magnesite under dry and wet conditions. The potential parameters for the carbonate and water species contain shell terms to model the polarizability of the oxygen atoms. These static calculations show that the surfaces undergo relaxation leading to the rotation and distortion of the carbonate groups with associated movement of cations. The dry surface energies are 0.322, 0.247, and 0.256 Jm−2 for calcite, dolomite, and magnesite respectively. The influence of water on the surface structure and energies has been investigated for monolayer coverage. When fully hydrated with a monolayer of water, the surface energy for calcite is reduced indicating a stabilization of the surface with hydration. The extent of carbonate group distortion is greater for the dry surfaces compared to the hydrated surfaces, and for the dry calcite relative to that for dry magnesite.

We used a mathematical model of crystal growth of [1] for the description of an eutectic pattern [2]. But the stationary problem gives physically unrealizable solutions (fig. 1) for values of system parameters corresponding to real experiments. Now known models [1,3-7] of crystal growth, used for a research of the interface stability of directed crystallization, not take into account of an external temperature field too. As examples of application of these models the regimes of crystal growth are usually used. The purpose of this work - to construct a model of a binary melt crystallization taking into account an external temperature field. Within the framework of this model we deduce analytical dependence of period of the eutectic structure on parameters of the system. We demonstrate, that for real parameters of the system, the parameters of the external temperature field weakly influence period of the eutectic pattern. This outcome is observed in experiments. We also explain the reason of joint emerging eutectic and dendrite of a structure for want of growth of eutectic crystals. We also explain the reason of joint both eutectic growth and dendrite growth under eutectic growth.

Applying atomic force microscopy in single string scanning mode, dependence of fluctuations of step shifts on KDP crystal faces on time was determined during crystallization from solution. It was shown that fluctuation amplitude grows proportionally to t1/4. On prism faces fluctuations at dissolving were bigger than at growth and bigger than on bipyramid faces. Amplitude of fluctuations was not dependent on distance between steps. Interpretation of experimental results and computation of elementary parameters of crystallization was done based on theory of V.V.Voronkov.

Micropatterned self-assembled monolayers (SAMs) that serve as substrates for nucleation provide a way of controlling various aspects of the crystallization process with a previously unreachable precision. We focus on crystallization of calcite (CaCO3) on SAMs of HS(CH2)nX (X = CO2H, CH3, SO3H, OH, N(CH3)3Cl) supported on Ag and Au. Fine-tuning of the crystallographic orientation of the forming crystals has been achieved by using different functional groups and metal substrates. By patterning SAMs with microregions having different nucleating activities and proper geometry, it is possible to confine crystallization to well defined, spatially delineated sites. This method provides means to fabricate arbitrarily patterned calcitic arrays with controlled density of nucleation, crystallographic orientation, and crystal sizes. The experimental conditions and the mechanisms discussed can be applied to the templated nucleation of a wide range of inorganic materials.

Free base phthalocyanine films have been grown on glass substrates by organic molecular beam deposition. In situ post-growth annealing of the samples leads to the α → β1 transformation. Different transition states have been identified and their morphological properties studied by atomic force and optical microscopy. The transition occurs via a discrete number of nucleations and is preceded by an elongation of the α crystallites. The β1 crystallites grow but are confined to domains of similar orientation. Increased thickness produces larger domains and better orientation, while only partial transformation occurs below 94 nm.

High-Resolution Transmission Electron Microscopy (HRTEM) results show a strong crystal-chemical and defect dependence on the mode of dissolution of synthetic heterogenite (CoOOH) particles. As-synthesized heterogenite particles are micron-size plates (aspect ratio ∼ 1/30) constructed of crystallographically oriented ∼ 3-nm primary particles or are single ∼ 21-nm unattached heterogenite platelets (aspect ratio ∼1/7). Reductive dissolution, using hydroquinone, was examined in order to evaluate morphology evolution as a function of reductant concentration. Two end-member modes of dissolution were observed: 1) non-specific dissolution of macroparticles and 2) preferential dissolution along misoriented boundaries. In the case of non-specific dissolution, average macrocrystal size and morphology are not altered as building block crystals are consumed. The result is web-like particles with similar breadth and shape as undissolved particles. Preferential dissolution involves the formation of channels or holes along boundaries of angular misorientation. Such boundaries involve only a few degrees of tilt, but dissolution occurs almost exclusively at such sites. Energy-Filtered TEM thickness maps show that the thickness of surrounding material is not significantly different from that of undissolved particles. Finally, natural heterogenite from Goodsprings, Nevada, shows morphology and microstructure similar to those of this synthetic heterogenite.

A novel technique for examining kinetic roughening of crystals is described, and applied to the study of the prism plane of ice in contact with aqueous fructose solution. The technique can be generally applied to crystals that roughen at low driving forces. Since the residual driving force for growth utilised is that due to Ostwald ripening, this technique also facilitates simultaneous quantification of ensemble growth kinetics and crystal anisotropy during ripening. The driving force required for kinetic roughening, and the step, or ledge, free energy of this plane of ice show an approximately linear variation with temperature over the experimental temperature range −13°C to −17°C. Whilst we can conclude that the thermodynamic roughening temperature (TR) is higher than −13°C, its precise value, and conformance or otherwise of the roughening transition with Kosterlitz Thouless scaling, can not be concluded from the current data set.

Chemical affinity-based rate laws are used across the geochemical and materials communities to quantify mineral/material corrosion and growth kinetics. These rate expressions are founded in assumptions regarding reaction mechanism with little evidence for surface processes. Using Atomic Force Microscopy (AFM), this study demonstrates the dependence of growth kinetics upon the structures of dislocation sources. In situ observations show that the dominant mode of growth occurs by hillock development initiated at complex sources. Derivations of surface process-based rate expressions show a complex dependence of rate on chemical affinity. This dependence is approximated by second order affinity-based rate laws only under the special conditions that 1) growth proceeds by development of single sourced spirals and 2) growth occurs at very near equilibrium conditions where spiral formation is the only operative mechanism. This suggests that growth experiments that measure temporal changes in solution chemistry yield a composite rate that arises from the contributions of the different hillock types. Hence, chemical affinity-based rate laws do not generally give meaningful interpretations of growth mechanism. By combining direct observations with macroscopic methods that monitor temporal changes in solution chemistry, rate laws with greater predictive capabilities may be possible.

Oriented gases of biopolymers in simple, single crystal hosts might be used to measure anisotropic molecular properties of analytes that could not otherwise be crystallized. Here we show two types of crystals as examples of the single crystal matrix isolation of biopolymers: green fluorescent protein in α-lactose monohydrate as a model system for studying the kinetic stabilization of biopharmaceuticals, and adenosine phosphates in potassium dihydrogen phosphate, a first step in the matrix isolation of oligonucleotides. In each case, the hosts undergo compositional zoning – both intersectoral and intrasectoral – during growth from solution. Intrasectoral zoning is evident by the selective luminescence of adjacent vicinal slopes of growth active hillocks. Nucleotides furthermore distinguish between symmetry related growth sectors enantioselectively.

Two crystal forms, orthorhombic and cubic, of satellite tobacco mosaic virus have been investigated. Atomic force microscopy showed that the orthorhombic crystals were characterized by a high density of point defects, while the cubic crystals were practically defect-free. Nonetheless, orthorhombic crystals diffract to a high resolution of 1.8 Å while the cubic crystals diffract to only about 4 to 6 Å resolution. Differences in the properties of viruses incorporated into the two crystal structures were demonstrated by growth kinetics studies. It appears that physical and chemical treatments applied to protein and virus solutions during their extraction and purification introduce a variety of specific structural changes and that these alterations may then affect the diffraction properties of resultant macromolecular crystals.

A two-dimensional Fourier transformation, FT, is used to isolate two different lattice structures within one scanning probe microscope, SPM, image. The isolated structures are then used to create a two-color map that encodes the presence of these structures within the image. The color map is normalized in brightness and then used to color-code the original black and white SPM data. The distribution of different structures becomes obvious, while all original brightness information is preserved in this combined image.

The interface between dewet glass droplets and the free surface of a crystal and the interface between the intergranular glass and adjoining crystalline grains have been examined with particular emphasis on the influence of the crystallography of the free surface and the grain boundary. The wetting of liquid on the free surface has been shown to depend on the surface structure. The migration of boundaries containing a liquid phase has been studied. The migration is initiated by the difference in surface energy of the bounding planes. Faceting of the grain boundary planes has been examined. It is proposed that the boundary migrates by the motion of the facets.

Powder X-Ray diffraction (XRD) has been used to study multilayered structures grown by, organic molecular beam deposition based on the molecular materials PTCDA and metal-free phthalocyanine (H2Pc). Double layers of different polymorphic forms (α, β1 and β2) of H2Pc indicate that the structure of the second layer is determined by the properties of the first layer. It is also shown that the first layer completely disrupts the crystallinity of the second layer in heterostructures containing PTCDA and H2Pc. The implication is that a strong templating effect occurs during the growth of multilayer molecular thin film structures.

In situ interference technique is used for a study of morphology and growth kinetics of a pyramidal face of KDP crystals with dye Chicago Sky Blue. It is shown that the impurity is captured by a crystal when its concentration in the solution exceeds a certain temperature depended value. In the presence of impurity the face loses its stability with increasing of supersaturation. Further increase of supersaturation leads to the restore and subsequent loss of stability. The experimental results are interpreted in the framework of earlier developed model for a crystal growth in the presence of the easily desorbed mobile impurity. The parameters characterizing the adsorption behavior of mobile impurity and its capture have been determined.

Vacuum packaging is a very important issue for vacuum microelectronics devices, especially for field emission displays. Emission current from the field emitter array (FEA), however, is known to decrease significantly after the vacuum packaging process. The current decrease is caused by heating treatment in the vacuum sealing process. In the present paper, the effect of the heating treatment on Si FEA was investigated and CHF3 plasma treatment was proposed for avoiding the problem. The Si FEA was exposed to plasma for 15sec and emission characteristics were measured before and after the vacuum sealing process using frit. It was confirmed that CHF3 plasma treatment was very effective for avoiding the emission degradation of the Si FEA. Details of the heating damage and CHF3 plasma treatment are described.

This paper is a short review of recent studies, which were undertaken to investigate interactions of amelogenin with octacalcium phosphate (OCP), and apatite. OCP crystals were grown using two independent experimental systems; (a) in a 10% gelatin gel, containing 0-2% amelogenin, where the crystals were formed in a double-diffusion chamber, and (b) in a 10% pure amelogenin gel, where crystal growth took place in between a cation-selective and a dialysis membrane. Apatite crystals were grown from a supersaturated calcifying solution on a bioactive glass in the absence (SCSB) and the presence of amelogenin (SCSrM179). It was found that OCP crystals formed in 10% gelatin gel containing 1-2% amelogenin were longer (3-5 times larger in aspect ratio) than the OCP crystals formed in 10% gelatin without amelogenin. A profound effect was that found in the cation selective membrane system when 10% amelogenin inhibited the growth morphology in a specific manner. Affected crystals had a length to width ratio twice larger than that of control crystals while the width to thickness ratio was about 1/12 of that of the control crystals. Amelogenin promoted the formation of bundles of lengthwise apatite crystals, which were all oriented parallel to their c axes when grown on SCSrM179. It was found that individual apatite crystals within those bundles adopted an elongated, curved shape. The data presented here suggest that amelogenin nanospheres modulate the growth morphology of apatite and OCP crystals and indicate significant functional roles for amelogenin proteins during the in vivo oriented growth of enamel crystallites.

We review here the recent characterization of vacuum deposited monolayer and multilayer thin films of two different perylenetetracarboxylic-dianydride-bisimides (Cn-PTCDI; n =4,5), quinacridone, and two new bis-(N-alkyl)-quinacridone dyes (DIQA and DEHQA) on single crystal alkali halides using a combination of in situ luminescence spectroscopies and ex situ tapping mode AFM. Flat lying monolayer structures are indicated for PTCDA on the (100) faces of NaCl, KCl and KBr, for C4-PTCDI on KCl, for C5-PTCDI on both KCl and KBr and for DIQA on both KCl and KBr. Coherent thin films, exhibiting layer-by-layer growth can be achieved for PTCDA on all substrates, for C4-PTCDI on KCl and for DIQA on both KBr and KCl. Both C4-PTCDI and DIQA appear to fulfill the requirements for dyes which exhibit layered growth with the molecular plane inclined at steep angles to the surface normal.

Crystals reveal a large variety of shapes, depending on the chemical composition and the structure of crystals, and the growth conditions. To predict precisely the growth morphology of crystals remains a challenging issue for both academia and industry. In this paper, the principles for predicting the growth morphology of crystals based on the best available theories are highlighted and demonstrated.