Crystallographic morphology

Owens C, Pytlewski LL, Mikulski CM, et al. 1979. X-ray crystallographic, morphological and thermal-decomposition studies of 2-1 adduces of diisopropyl methylphosphonate with stannous and stannic halides. Journal of Inorganic Nuclear Chemistry 41(9) 1261-1268. 

The crystallographic morphology of the films exhibits dominance of cubic 100 and octahedral 111 surfaces and 111 twin planes. Cubo-octahedra exhibiting both 100 and 111 surfaces are common. 

Metals - powders Smallest representative size sold May need to consider different sources if yielding different crystallographic / morphologic properties... 

Fig. 8 Equilibrium crystallographic morphology of MgCl2 estimated from surface energies of DFT-D calculations (reproduced from [37])...

It is well known that with a photolithographic-based process one can obtain microchannels having a cross section fixed by the orientatiOTi of the wafer crystal planes for example, the microchannels etched in (100) silicon using a KOH solution have a trapezoidal cross section with an apex angle of 54.74° imposed by the crystallographic morphology of the (100) silicon. 

In the broad context of feeing the MOF crystal functionalization and growth, the use of the sol-gel method would offer enormous advantage over other methods. The reason relies on the fine tunability of chemical, crystallographic, morphological, functional properties of sol-gel-based materials [30-32]. Sol-gel technology has been used to prepare oxide systems to form nano/microparticles [33-35], fibers [36-38], thin films [39-41], and monoliths [42-44]. The wide options of structures and compositions afford sol-gel-based materials to be applied to broad applications such as controlled release, catalysis. 

Thin films of metals, alloys and compounds of a few micrometres diickness, which play an important part in microelectronics, can be prepared by die condensation of atomic species on an inert substrate from a gaseous phase. The source of die atoms is, in die simplest circumstances, a sample of die collision-free evaporated beam originating from an elemental substance, or a number of elementary substances, which is formed in vacuum. The condensing surface is selected and held at a pre-determined temperature, so as to affect die crystallographic form of die condensate. If diis surface is at room teiiiperamre, a polycrystalline film is usually formed. As die temperature of die surface is increased die deposit crystal size increases, and can be made practically monocrystalline at elevated temperatures. The degree of crystallinity which has been achieved can be determined by electron diffraction, while odier properties such as surface morphology and dislocation sttiicmre can be established by electron microscopy. 

The catalytic tests show that, over the Pt(l 0 0)/Al2O3 catalyst, the formation of CO and NH3 is largely prevented, whereas the yield of N2O increases compared with the Pt(polycrystalline)/Al203 catalyst. These main differences observed should be ascribed to the morphological differences between two catalysts, i.e., the dominant orientation of the crystallographic facets and the average size... 

Evaluation of the morphology of a pharmaceutical solid is of extreme importance, since this property exerts a significant influence over the bulk powder properties of the material. In addition to providing insights into the micromeritic properties of the solid, microscopy can also be used to develop preliminary estimations of the particle-size distribution. A determination can be easily made regarding the relative crystallinity of the material, and it is often possible to deduce crystallographic information as well. Unknown particulates can often be identified solely on the basis of their microscopic characteristics, although it is useful to obtain confirmatory support for these conclusions with the aid of microscopically assisted techniques. 

---