Tetra gonality

Stmcture tetra- gonal hexa- gonal ortho- rhombic tetra- gonal ortho- rhombic... 

The first studies of dendrimer-encapsulated metal nanoparticles focused on Cu [82]. This is because Cu + complexes with PAMAM and PPI dendrimers are very well behaved and have easily interpretable UV-vis and EPR spectra. For example, Fig. 4a shows absorption spectra for Cu + coordinated to different ligands. In the absence of dendrimer and in aqueous solutions Cu + exists primarily as [Cu(H20)g] +, which gives rise to a broad, weak absorption band centered at 810 nm. This corresponds to the well-known d-d transition for Cu in a tetra-gonally distorted octahedral or square-planar ligand field. 

Microcrystals exhibit properties distinctly different from those of bulk solids. The fractional change in lattice spacing has been found to increase with decreasing particle size in FejOj. Magnetic hyperfine fields in a-FejOj and FejO are lower in the microcrystalline phase compared to those of the bulk crystalline phases. The tetra-gonality (i.e. the departure of the axial ratio from unity) of ferroelectric BaTiOj decreases with decrease in particle size in PZT, the low-frequency dielectric constant decreases and the Curie temperature increases with decreasing particle size. The small particle size in microcrystals cannot apparently sustain low-frequency lattice vibrations. 

The X-band EPR spectra of vanadium-doped amorphous and PC tetra-gonal Ge02 have been observed even at room temperature (Table 8.8), but there were not recorded for PC hexagonal Ge02 neither at 298 K, nor at 77 K [184]. 

MUC2 tetra- gonal a=4,961 c=l, iA6 FeUCj Pulver (zwischen 1000- 1400 °C getempert) 65Ans... 

Tag4C tetra- gonal 0 = ) c= Martensit( ) E, diinne Filme, Struktur qualitativ 65V11... 

ThCj tetra- gonal 0=4,235 c= 5,408 [>1410- <1490] Pulver 64Lan 68Henl 65Ganl... 

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