Binary structures palladium

The binary compounds of palladium and platinum show a higher diversity of structures than found for the Rh-Ir and Ru-Os systems. Aside from several other reported binary phases, four general families can be distinguished ... 

Pair-of-dimer effects, chromium, 43 287-289 Palladium alkoxides, 26 316 7t-allylic complexes of, 4 114-118 [9JaneS, complexes, 35 27-30 112-16]aneS4 complexes, 35 53-54 [l5]aneS, complexes, 35 59 (l8)aneS4 complexes, 35 66-68 associative ligand substitutions, 34 248 bimetallic tetrazadiene complexes, 30 57 binary carbide not reported, 11 209 bridging triazenide complex, structure, 30 10 carbonyl clusters, 30 133 carboxylates... 

From binary alkali hydrides and platinum (palladium) sponge at 573 623 K under 0.8 bar (Pd compounds 70bar) hydrogen colorless powders, sensitive to air and moisture ordered structures (Figure 8) by npd on deuterides P4/mbm, Z = 2 isostmctural to RbsPdFs planar [PtELi] (or... 

Other binary hydrides can be formed with light elements, without improvement in performance. The structure of NiH is shown in Fig. 2.51. For heavy metals, only palladium has received some attention, due to rapid absorption and desorption at ambient temperature and pressure. However, only 0.6% hydrogen by mass is stored, which together with high metal cost makes this option unattractive. 

Palladium(O) compounds have a configuration and unlike most transition metals this oxidation state is dominated by phosphine complexes rather than carbonyls. In fact binary carbonyl complexes with palladium are unstable at room temperature. The highest coordination number known for Pd is four and [PdLj complexes adopt a square planar structure. Dissociation of ligands from [PdLJ occurs readily to generate the 16- and 14-electron species [PdLs] and [Pdl ] these are trigonal planar and linear respectively. Another notable feature of Pd° is that facile oxidation to cr Pd occurs. 

Binary addition elements, having in general Face-Centered-Cubic (FCC) crystal structures, stabilize the a-hydride phase against the P-hydride phase transition, reducing the problem of embrittlement, and also increase hydrogen permeability above that of pure palladium (see Table 14.2). 

Formation of superstructures of the binary rare-earth germanides The crystal structure of Ho26Pd4(Pd,Ge)i9 jc represents a substitutional variant of the Er26Ge23-j structure type. The difference between the two structures lies only in the replacement of germanium atoms by palladium atoms in positions 2(c) and 8(j) and the presence of a statistical distribution of Ce and Pd atoms in positions 2(c) and 8(i). Other isotypical ternary phases are not known. Only the compound Ce26Li5Gc23 -y, where the Li atoms occupy the 2(b) and 8(i) positions which are vacant in the previous phases, has a similar structure (table 5). 

TABLE 6 Transition temperatures (°C) of eight disc-shaped metallorganic compounds of the molecular structures 7 or 8 of whidi 7a-7e contain a super-disc core with the greatest diameter of 1.5 nm, two platinum or two palladium atoms, and different bridging units. Included are the binary mixtures of 7d and 7e with 2,4,7-hinitrofluorenone (5a) each exhibiting by induction die columnar nematic phase. 

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