The d9 ion is characterized by large distortion from octahedral symmetry
and the band is unsymmetrical, being the result of a number of transitions, which are by no means easy to assign unambiguously (Table 3).
The complexes of acetovaleric acid hydrazone [AVAH], acetylaldehyde valeric acid hydrazone [AAVAH], acetyl isovaleric acid hydrazone [AIVA] and acety aldehyde varaleric acid hydrazone [AAIVAH] complexes with Cu(II) and Ni(II) sulphate have been reported to be of distorted octahedral symmetry with a promising antibacterial activity (4).
The electronic spectra of the complexes in chloroform, as given in table 2 shows a single band for each of the complexes and are been assigned a [sup.6][A.sub.1g] [right arrow] [sup.4][A.sub.1g], and [sup.4][T.sub.2g](f) [right arrow] [sup.4][T.sub.2g](p) transitions for Fe and Co complexes respectively with octahedral symmetry (7).
Among the topics are electron crystallization, melting a magnetically induced Wigner electron solid and anyon properties, structure and forces in simple liquid metals, the quantum theory of pure liquid metals as two-component systems, Thomas Fermi fields for molecules with tetrahedral and octahedral symmetry
, electron theory of interaction between point defects in metals, constructing non-local energy density functionals, and foundations of Walsh's rules for molecular shape.
The second model was advanced by Wang and Hall; Wang & Hall (1982), Mestl & Srinivasan (1998), who pointed out that the adsorbed molybdate species depend on the impregnation solution pH: at high pH, only tetrahedral molybdate ions are adsorbed onto the [gamma]-[Al.sub.2][O.sub.3] surface, whereas at low pH the adsorption of polymolybdate ions (octahedral symmetry
In addition, a sextet of lines in g = 2 can be appreciated, which is typical of [Mn.sup.2+] species with distorted octahedral symmetry
(Tus!ar et al.