Group IV chalcogenides

In Fig. 2.42 results from the ATHAS laboratory on group IV chalcogenides are listed [18]. The crystals of these compounds form a link between strict layer stractures whose heat capacities should be approximated with a two-dimensional Debye function, and crystals of NaCl stracture with equally strong bonds in all three directions of space and, thus, should be approximated by a three-dimensional Debye function. As expected, the heat capacities correspond to the structures. The dashes in the table indicate that no reasonable fit could be obtained for the experimental data to the given Debye function. For GeSe both approaches were possible, but the two-dimensional Debye function represents the heat capacity better. For SnS and SnSe, the temperature range for data fit was somewhat too narrow to yield a clear answer. 

Examples of Two- and Three-dimensional Debye Functions for Group IV Chalcogenides... 

Gaur U, Pultz G, Wiedemeier H, Wunderlich B (1981) Analysis of the Heat Capacities of Group IV Chalcogenides using Debye Temperatures. J Thermal Anal 21 309-326. Baur H, Wunderlich B (1998) About Complex Heat Capacities and Temperature-modulated Calorimetry. J Thermal Anal and Calorimetry 54 437 65. 

Abstract This review highlights how molecular Zintl compounds can be used to create new materials with a variety of novel opto-electronic and gas absorption properties. The generality of the synthetic approach described in this chapter on coupling various group-IV Zintl clusters provides an important tool for the design of new kinds of periodically ordered mesoporous semiconductors with tunable chemical and physical properties. We illustrate the potential of Zintl compounds to produce highly porous non-oxidic semiconductors, and we also cover the recent advances in the development of mesoporous elemental-based, metal-chalcogenide, and binary intermetallic alloy materials. The principles behind this approach and some perspectives for application of the derived materials are discussed. 

Kalinina IV, Fedin VP. Cubane chalcogenide complexes of group IV-VI metals Synthesis, structure, and properties. Russ J Coord Chem 2003 29 597-615. 

Chalcogenides of group IV and V elements form glasses, which constitute a major class of amorphous semiconductors. As a class of semiconductors, hydrogenated amorphous silicon and carbon constitute a... 

Jamison and Cosgrove [88] studied the friction characteristics of disulfides and diselenides of the following transition metals of Groups IV-VII Zr, Hf, Nb, Ta, Mo, W, Re. A film of the chalcogenide was bur-... 

The most important elemental constituents of amorphous semiconductors are Si and Ge in Group IV P, As, Sb and Bi in Group V and the chalcogenides (S, Se, and Te) in Group VI. Elements, compounds, or multi-component alloys varying widely in composition can be prepared in amorphous form variously by cooling a melt or condensing a vapor. 

Although there are similarities between the chemistry of the chalcogenide elements, the properties of selenium and tellurium clearly lie between those of non-metallic sulfur and metallic polonium. The enhancement in metallic character as the group is descended is illustrated in the emergence of cationic properties by polonium, and marginally by tellurium, which are reflected in the ionic lattices of polonium(IV) oxide and tellurium(IV) oxide and the formation of salts with strong acids. 

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