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Cyclic isomorphism

Since if is therefore an isomorphism, we have proven that any tree rooted on a cyclic state is identical to the tree rooted on the null configuration. I... [Pg.242]

Although we will not worry about the precise tree structure, we note that for all graphs, and therefore all additive rules, every cyclic state is a root of a tree which is isomorphic to the null tree (the one terminating on S = 0) ... [Pg.263]

This follows from the fact that all trees are isomorphic each of the cyclic states has an... [Pg.266]

Some of the information pertaining to a group is stored in property lists. Table I exemplifies how this looks for the simple case of the cyclic group of order three. (This would be isomorphic to the rotational subgroup of a molecule such as methyl fluoride. The operators (1 2 3) and (1 3 2) would correspond to the permutations of the three hydrogen nucleii numbered 1, 2 and 3. NIL, the language s symbol for the empty list, serves as the identity.)... [Pg.179]

Fergusson et al. were the first to report the existence of binary compounds with a general formula Se Sg in these melts. They carried out an extensive investigation by X-ray powder diffraction and by absorption spectroscopy in the infrared, visible, and ultraviolet regions over the whole composition range of molten mixtures of sulfur and selenium cooled down to 20 °C. They also examined phases obtained by recrystallization of the cooled melts from carbon disulfide. All phases were isomorphic with one of the allotropes of Sg and SCg indicating that the structures also consist of cyclic eight-membered molecules ... [Pg.180]

The M(DLD)3" complexes (M = Co, Rh, Cr) can be isolated as crystalline, x-ray isomorphous salts of the Me3PhN+ cation with two waters of hydration. The diamagnetism and electronic spectra of the Co(lII) complex are consistent with a d6 octahedrally coordinated ion. Cyclic voltametry shows quasi-reversible oxidation at +0.14 V (in CH2C12 versus Ag AgI). A separation between the anodic and cathodic waves of 0.60 V suggests that a reversible rearrangement occurs upon oxidation of the Co(DED)3 anion. An investigation of the oxidation product is currently underway. [Pg.437]

Clearly, this set forms a group Qe of order six the group is neither Abelian nor cyclic. A group with the same multiplication table as Q (perhaps to within a permutation of rows and columns) is said to be isomorphic to Q. ... [Pg.92]

There are only two groups of order 4 that are not isomorphous and so have different multiplication tables. Derive the multiplication tables of these two groups, G4 and G4. [Hints. First derive the multiplication table of the cyclic group of order 4. Call this group G4. How many elements of G4 are equal to their inverse Now try to construct further groups in which a different number of elements are equal to their own inverse. Observe the rearrangement theorem.]... [Pg.22]

Find the representations of the space group 227 (Fd3m or O],) at the surface point B(1/2 + /3, ( I 3, Vi + a), point group Cs= E ay. [Hints-. Use the method of induced representations. Look for an isomorphism of Cs with a cyclic point group of low order. The multiplication table of Cs will be helpful.]... [Pg.356]

The electrochemistry of the polymeric and isomorphous cobalt(II) and nickel(II) methylsquarates was also studied by Iwuoha et al. In aqueous solutions, they found evidence that both the nickel(II) methylsquarate and its cobalt analog were dissociated without any reversible redox processes occurring for the metal ions. However, the cyclic and Osteryoung square wave voltammograms, obtained using a Pt electrode for solutions of these complexes in dimethylformamide and dimethylsulfoxide, contained signals attributable to both ligand-based and metal-based redox processes 142). [Pg.285]

The isomorphism between and 4 provides a simple illustration to become familiar with the formal description of permutational groups. A permutational operation on four elements can be characterized as a sequence of cyclic permutations, e.g. a threefold axis running through atom 1 will map 1 onto itself and produce a cyclic permutation of the remaining three atoms. It is therefore denoted as (3,1). All threefold elements have the same cycle structure and in view of the complete transitivity of the set thus must belong to the same symmetry classes. In this way the elements of T4 can easily be identified as 4 operators, as shown in Table 1. The irreps themselves are also denoted as partitions of n, indicated between patentheses. Pictorially these partitions may be denoted by Young tableaux, as also indicated in the character table. [Pg.33]

Any cyclic group G is isomorphic to the additive group of integers modulo IGI. For any generator g, the exponentiation function expgix) = g is an isomorphism into G. The inverse is the discrete-logarithm function logg. In particular, G is Abelian, i.e., commutative. [Pg.213]

A number of substances of the ferrichrome family, containing three hydroxamic acid groups coordinated to a central ferric ion, have been isolated, mainly from microbial sources. These compounds contain a cyclic hexapeptide. Crystal structures for ferrichrome A, cyc/o[LSer-LSer-Gly-Tri ((5-N-methylglutaconyl-5-N-hydroxy-Orn)] (Figs. 11 and 12) (Zalkin et al, 1966), the isomorphous alumichrome A (van der Helm et ai, 1980), and more recently ferrichrysin [LSer-LSer-Gly-tri(5-JV-acetyl- -N-hydroxy-Orn)] (Norrestam et al, 1975) and ferrichrome (Loghry and van der Helm, 1978) have been determined and show that the molecules are essentially isostruc-tural. In these molecules, the ferric ion has approximate octahedral coordination to the six oxygen atoms of the three 5-N-acetyl-5-N-hydroxy or the... [Pg.17]


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See also in sourсe #XX -- [ Pg.213 ]




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Isomorphic

Isomorphism

Isomorphous

Isomorphs

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