Triels

Toward Quasicrystals and Their Approximants 3.1 Polar Intermetallics Containing the Triels... 

Where might one find new AC/QC materials Our earlier extensions of the p-element components in Zintl-type compounds to the triels (Al, Ga, In, Tl) (beyond the so-called Zintl boundary ) as well as the inclusions of late transition metals had already given us some significant glimpses of new and appropriate chemistry and structures [46,51]. In addition, some examples were already in the literature for Ga [44], In contrast, the anion or intermetallic chemistry of aluminum [45] stands apart from that of the three heavier group members (Ga, In, and Tl) and will not be considered here significantly. 

Remarks on the crystal chemistry of the triel elements (Al, Ga, In, Tl). Tables 5.65a, 5.65b and 5.65c summarizes the crystal data of typical phases pertaining to the alloys of the 13th group. A few specific comments are in the following. 

Notes on cluster phases in triel alloys. Li and Corbett (2004) have shortly reviewed the systematic and extensive experimental and theoretical work carried out by Corbett and co-workers (see for instance Corbett 1996). Considering alkali metal-triel alloys, they underlined, particularly for Ga, In and Tl, the richness of their chemistry (see also 5.3.4.4). Gallium forms many anionic network structures (and only a few phases containing isolated cluster units), indium gives several examples of both network and discrete cluster structures, thallium forms especially discrete clusters (Tl , T157A Tl , Tl , Tl(f, Tl ). 

The triels made by the directions of Cuaptat. succeeded so far as the matter examined by him was employed but when another volcanic product came to be used, the results were bad, the proportions being deranged. A vory simple analysis would have prevented all trouble, and would have preserved their proper rank to these volcanic matters, the excellent effects of which have been demonstrated by a sufficiently long experience. 

L. Rey, Les orientations nouvelles de las lyophilisation. Aspects theoriques et indus-triels de la lyophilisation. Hermann, Paris, 1964, pp. 621-653. 

Trimethyl- (TriML) and triethyllead (TriEL) compounds were obtained from Alfa products (Johnson Matthey) and their purity was verified as follows carbon, hydrogen and chloride relative masses in the TriML and TriEL calibrants were determined by elemental microanalysis the chloride concentration was determined by ion chromatography. Total lead was determined in the calibrants by electrothermal atomic absorption (ETAAS) using two different acid digestion procedures (concentrated nitric... 

The second interlaboratory study generated detailed discussions one ETAAS technique employed did not include a separation step but the participant stated that EDTA extraction would only extract organic lead compounds this technique was considered to be suitable for the analysis of a simple solution containing only one lead compound but would not be suitable for mixtures of lead species, e.g. the technique would not allow the separation of TriML and TriEL in a natural rainwater sample. In cases where different organolead compounds are to be determined in natural samples or solutions containing different lead compounds, ETAAS should be coupled to a separation technique, e.g. GC or HPLC. 

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