Lattice work packings

Martensitic phase transformations are discussed for the last hundred years without loss of actuality. A concise definition of these structural phase transformations has been given by G.B. Olson stating that martensite is a diffusionless, lattice distortive, shear dominant transformation by nucleation and growth . In this work we present ab initio zero temperature calculations for two model systems, FeaNi and CuZn close in concentration to the martensitic region. Iron-nickel is a typical representative of the ferrous alloys with fee bet transition whereas the copper-zink alloy undergoes a transformation from the open to close packed structure. ... 

Among MC lattice models of the double layer, it is also worth mentioning the work of Nazmutdinov et al. (1988), who used a lattice model involving two mono-layers of water molecules on the surface of an electrode, forming a hexagonal close-packed array. The interaction of each water molecule in contact with the metal surface (assumed to be Hg) was taken from quantum-mechanical calculations. Information was obtained concerning the relative numbers of molecules with different numbers of hydrogen bonds, and it was concluded that the hypothesis of an icelike state of water in a monolayer on Hg is rather unlikely. 

Finally, the question of the ability of the modeling methods to predict the crystal lattice (i.e., the unit cell) from the conformation of the chain should be addressed, despite the expected computational difficulties. Based on previous work, in which the prediction of the unit cells of all four cellulose polymorphs in both parallel and antiparallel chain packing polarities was... 

SOLID. Matter in its most highly concentrated form, i.e., the atoms or molecules are much more closely packed than in gases or liquids and thus more resistant to deformation. The normal condition of the solid state is crystalline structure—the orderly arrangement of the constituent atoms of a substance in a frame work called a lattice, See also Crystal. Crystals are of many types and normally have defects and impurities that profoundly affect their applications, as in semiconductors, The geometric structure of... 

The nitrides and carbides of titanium and zirconium and the carbide of hafnium are extremely hard substances, resembling metals both in appearance and in electrical conductivity. Their formulae approach AxBh but some departure from stoichiometry is possible. Each of these refractory substances has the sodium chloride structure, described alternately (p. 190) as cubic close-packed arrays of metal atoms with the small nonmetal atoms in the octahedral holes. Note, however, that the parent metals themselves do not have cubic close-packed structures. Thus, the older view of such nitrides and carbides as lattices of the parent metals that are expanded to accommodate nitrogen or carbon atoms in the holes (interstices) is not admissible. The nature of the bonding in such refractory nitrides and carbides appears to be linked to the nature of bonding in metals in general, an important and interesting topic, but best pursued in more advanced works. 

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