Crystalline solids solid-state chemistry

Kroger, RA. and Vink, H.J. (1956) Relations between the concentrations of imperfections in crystalline solids, Solid State Phys. 3, 307. The original proposal of the notation that is now universally used to describe charged point defects. This is an invaluable paper when you have time to study it. The official notation is given in the lUPAC Red Book on the Nomenclature of Inorganic Chemistry, Chapter 1-6. Smyth, D.M. The Defect Chemistry of Metal Oxides, Oxford University Efi-ess, Oxford 2000. Clear and at the right level. 

Niederberger, M., Gamweitner, G., Pinna, N. and Neri, G. (2005) Non-aqueous routes to crystalline metal oxide nanopartides formation mechanisms and applications. Progress in Solid State Chemistry, 33 (2—4), 59—70. 

F. Khoury and E. Passaglia, The morphology of crystalline synthetic polymers. In N.B. Hannay (Ed.), Treatise on Solid State Chemistry, 3rd ed., Plenum Press, New York, 1976, p. 335. 

In the field of solid-state chemistry an important group of substances is represented by the intermetallic compounds and phases. In binary and multi-component metal systems, in fact, several crystalline phases (terminal and intermediate, stable and metastable) may occur. A few introductory remarks about these substances will be presented in relation to the mentioned figures. 

Almost all the crystalline materials discussed earlier involve only one molecular species. The ramifications for chemical reactions are thereby limited to intramolecular and homomolecular intermolecular reactions. Clearly the scope of solid-state chemistry would be vastly increased if it were possible to incorporate any desired foreign molecule into the crystal of a given substance. Unfortunately, the mutual solubilities of most pairs of molecules in the solid are severely limited (6), and few well-defined solid solutions or mixed crystals have been studied. Such one-phase systems are characterized by a variable composition and by a more or less random occupation of the crystallographic sites by the two components, and are generally based on the crystal structure of one component (or of both, if they are isomorphous). 

Clathrate formation is very attractive for exploitation in solid-state chemistry. It allows one to modify in a simple way the environment of the guest molecule, to place this molecule in a crystalline phase with a structure different from its own (one structure may be chiral, and the other not), and even to achieve a stable crystalline structure at a temperature above the melting point of the pure guest. Some of the variety available for a single compound, acetic acid, is... 

If the utilization of weak noncovalent interactions leading to molecular aggregations is a general principle in supramolecular chemistry, and periodicity is a general prerequisite in the crystalline state, then periodically distributed noncovalent interactions constitute the basis of molecular crystal engineering [1]. In other words, molecular crystal engineering can be considered as supramolecular solid-state chemistry, again based on weak noncovalent interactions. 

It is important to point out that a combination of techniques is often necessary to understand a phenomenon fully or solve a structural problem in solid state chemistry. All the tools of solid state chemistry generally employed to investigate crystalline solids... 

Solid state chemistry of potentially important waste forms is covered in the fifth section. Solid state reactions can determine the oxidation state and physical and chemical stability of radionuclides in various host waste forms. This information can be used to evaluate the utility of crystalline materials as potential hosts for radioactive wastes. 

In spite of the great interest in the phenomenon of polymorphism and of the increased research activity beyond the boundaries of organic solid-state chemistry, it is a fact that only a few molecular compounds possess several crystalline forms, whereas for many other tens of thousands of molecular compounds only one crystalline form is known. In other words, why are there so few molecular crystals polymorphs The often quoted association between number of known forms and the time and energy spent in searching for them put forward by McCrone probably contains the answer to this question. It is probable that if thorough (combinatorial ) crystallization experiments were carried out on any given molecular species or molecular salt, alternative crystalline forms would be found. It is probable but not certain. 

Phosphorus has an even wider range of oxoacid chemistry, and a commensurately wide range of phosphates, phosphites, polyphosphates, hypophosphites, and so on of the alkali metals are preparable. Sodium and potassium are the most common cations used, largely because of their availability and low cost. The cation often has little effect on the properties and applications, which are covered in Phosphates Solid-state Chemistry. Most form a variety of crystalline hydrates, which have been well covered in previous treatments and need not be repeated here. Trae to form, lithium is the exception, forming no stable hydrates with phosphorus oxoanions. 

Microstructurally, alloys are composed of alloy constituents that include alloy phases and, in some cases, unalloyed metals. Crystalline alloy phases can be subdivided into intermetallic phases, metal-nonmetal compounds such as borides or carbides see Borides Solid-state Chemistry Carbides Transition Metal Solid-state Chemistry), and terminal or complete solid solutions. 

Glasses and ceramics are inorganic materials that have been produced for thousands of years see Oxides Solid-state Chemistry and Noncrystalline Solids). Traditionally they are made from natural raw minerals such as clays or sand. Crystalline ceramics are shaped by adding water to clays in order to produce a plastic material and then heated in a furnace. Amorphous glasses are made from the melt and shaped by moulding near their softening temperatme. In both cases, high temperatmes are required. 

Solid-state chemistry uses the same principles for bonding as those for molecules. The differences from molecular bonding come from the magnitude of the molecules in the solid state. In many cases, a macroscopic crystal can reasonably be described as a single molecule, with molecular orbitals extending throughout. This description leads to significant differences in the molecular orbitals and behavior of solids compared with those of small molecules. There are two major classifications of solid materials crystals and amorphous materials. Our attention in this chapter is on crystalline solids composed of atoms or ions. 

Khoury F, Passaglia E (1976) Treatise on solid state chemistry, vol 3. In Hannay NB (ed) Crystalline and noncrystalline solids, Chap 6. Plenum, New York... 

Transition metal clusters, however, need still to be tested in the engineering of crystalline materials. Crystal engineering has been defined as the capacity to make crystals with a purpose. In transition metal cluster chemistry this purpose is that of utilizing the distinct characteristics mentioned above to construct crystals that can function as the result of the inter-cluster interactions. To do this the experimentalist needs to conceive ways of directing the crystal-building process towards given architectures, i. e. needs to learn how to make non-covalent crystal synthesis. Clearly, the growth and success of a solid-state chemistry of transition metal clusters depends crucially on a close interaction between synthesis, theory, solid state characterization, and evaluation of properties. 

At present, a newcomer to solid-state chemistry might therefore believe that this science must have been a key proponent in challenging quantum mechanics (and quantum chemistry, too) for the solution of solid-state chemical problems. Strangely, this is not at all the case. Let us remind ourselves that the puzzle of chemical bonding was ingeniously clarified in 1927, not for a crystalline solid but for the hydrogen molecule. The rapidly emerging scientific discipline, quantum chemistry, also focused on the molecular parts of chemistry both because of technical and "political" reasons first, the most important quantum-chemical workhorse (Hartree-Fock theory) has been particularly resistant to adaptation to the solid state (see Section 2.11.3) and, second, we surely must be aware of the fact that the solid-state chemical commimity is limited in size such that the number of "customers" for quantum chemists is relatively small. As a sad consequence, the solid-state chemists have been left alone for some... 

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