Formulae solid state structures

In order to specify the structure of a chemical compound, we have to describe the spatial distribution of the atoms in an adequate manner. This can be done with the aid of chemical nomenclature, which is well developed, at least for small molecules. However, for solid-state structures, there exists no systematic nomenclature which allows us to specify structural facts. One manages with the specification of structure types in the following manner magnesium fluoride crystallizes in the rutile type , which expresses for MgF2 a distribution of Mg and F atoms corresponding to that of Ti and O atoms in rutile. Every structure type is designated by an arbitrarily chosen representative. How structural information can be expressed in formulas is treated in Section 2.1. 

The favorable bismuth-sulfur bond translates into thermal and hydrolytic stability for the thiolates of bismuth, which are currently more numerous than the alkoxide derivatives (Table II). Various monomeric trithiolates have been identified, and most adopt predictable structural formulas, although the solid-state structures reveal interesting intermolecular and intramolecular interactions. 

Nitrosyl complexes of formula [Ru(NO)Cl3(diphos)] in which diphos = dppm, dppe, dppp, or (Z)-l,2-bis(diphenylphosphino)ethene have been synthesized. Although P NMR spectroscopic data are consistent with a fac isomer in each case, the solid-state structure of [Ru(NO)Cl3(dppp)]... 

The solid-state structural formula is K[fLO (OH)J H20 (123), which is analogous to that found in sodium pentaborate (5). 

Despite the interest in group 2 bis(alkoxides) and bis(/3-diketonates) as precursors to metal oxides via CVD routes, systematic studies that correlate their structure and volatility still are few. The solid-state structures of many bis(alkoxides) used for CVD work are not known, and the identity of the materials may vary greatly depending on then-mode of preparation. As shown above, the widely used bis(/3-diketonate) derivative Ba(tmhd)2 for example, has that formula only if prepared under rigorously anhydrous conditions in the presence of moisture the pentanuclear cluster Ba5(tmhd)9(H20)3(OH) can form. Such uncertainties make the identification of trends in volatilities difficult. 

The Cu ion is classified as a soft acid (see Hard Soft Acids and Bases), which predicts reasonably well the types of ligands that will be most stabilizing and are, thus, commonly observed in Cu complexes. The preference of Cu for softer ligands is quite apparent in the homoleptic complexes, for instance the halides discussed above. Polynuclear compounds are quite commonly seen in the chemistry of Cn. Thus, the solid-state structure cannot be reliably predicted from the reaction stoichiometry or from the empirical formula of the resulting compound. The careful selection of ligands, for instance, an appropriate macrocyclic ligand can ensnre the formation of a mononuclear complex if one is desired. 

IR-4.2.3 Structural formulae and the use of enclosing marks in formulae IR-4.2.4 Formulae of (formal) addition compounds IR-4.2.5 Solid state structural information IR-4.3 Indication of ionic charge IR-4.4 Sequence of citation of symbols in formulae IR-4.4.1 Introduction IR-4.4.2 Ordering principles IR-4.4.2.1 Electronegativity IR-4.4.2.2 Alphanumerical order IR-4.4.3 Formulae for specific classes of compounds IR-4.4.3.1 Binary species... 

The formula of Nb3lj can be written as Nb3lg Ig 2- Explain how this can be translated into a description of the solid state structure of the compound. 

Summary The bidentate metal disiloxides of general formula LMCI2 [M = Ti, Zr L = (1)-2H] (3) were readily prepared from the reaction of (MesSOzHOSi-SiMer-SiOH(SiMe3)2 [LH2] (1) with M(NEt2)4 and subsequent addition of MCU (M = Ti, Zr), respectively. The solid-state structures of 3 were determined by X-ray crystallography. 

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