Structure linear

One reason that the symmetric stretch is favored over the asymmetric one might be the overall process, which is electron transfer. This means that most of the END trajectories show a nonvanishing probability for electron transfer and as a result the dominant forces try to open the bond angle during the collision toward a linear structure of HjO. In this way, the totally symmetric bending mode is dynamically promoted, which couples to the symmetric stretch, but not to the asymmetric one. 

Minimal END has also been applied to a model system for intramolecular electron transfer. The small triatomic system LiHLi is bent C2v structure. But the linear structure presents an unrestricted Haiti ee-Fock (TJHF) broken symmetry solution with the two charge localized stmctures... 

Carbon dioxide has a linear structure. The simple double-bonded formula, however, does not fully explain the structure since the measured carbon-oxygen bond lengths are equal but intermediate between those expected for a double and a triple bond. A more accurate representation is, therefore, obtained by considering carbon dioxide as a resonance hybrid of the three structures given below ... 

The CS2 is then removed, after cooling, by a solvent. The molecule has a covalent linear structure S==C=S. 

The ROSDAL syntax is characterized by a simple coding of a chemical structure using alphanumeric symbols which can easily be learned by a chemist [14]. In the linear structure representation, each atom of the structure is arbitrarily assigned a unique number, except for the hydrogen atoms. Carbon atoms are shown in the notation only by digits. The other types of atoms carry, in addition, their atomic symbol. In order to describe the bonds between atoms, bond symbols are inserted between the atom numbers. Branches are marked and separated from the other parts of the code by commas [15, 16] (Figure 2-9). The ROSDAL linear notation is rmambiguous but not unique. 

Hydrogenation of polybutadiene converts both cis and trans isomers to the same linear structure and vinyl groups to ethyl branches. A polybutadiene sample of molecular weight 168,000 was found by infrared spectroscopy to contain double bonds consisting of 47.2% cis, 44.9% trans, and 7.9% vinyl. After hydrogenation, what is the average number of backbone carbon atoms between ethyl side chains ... 

AA and BB monomers and also AB monomers invariably react to form predominantly linear structures in all but the rather special case where the ring structure in reaction (5.CC) has a value of 1 = 5 or 6. This explains why so many of the monomers in step-growth polymerizations are tetra-, hexa-, and decamethylene compounds. 

Those which have an essentially linear structure on to which are attached epoxide groups—the acylic aliphatic epoxide resins. 

The observed equilateral triangular 3-centre, 2-electron structure is more stable than the hypothetical linear structure, and the comparative stability of the species is shown by the following gas-phase enthalpies ... 

Molecular construction for a protein chain is just about impossible using the Z-matrix (unless you are particularly good at crossword puzzles). As 1 mentioned in Chapter 10, there are also immense practical difficulties associated with symmetric, cyclic and linear structures, and as time went by people began to question the use of the Z-matrix. 

Hie first effect has been exploited in numerous ligand-accelerated [30], enantioselective 1,2-additions of RyZn reagents to aldeliydes [26]. Dimetliylzinc, for example, has a linear structure and is not reactive towards aldehydes or ketones. Upon coordination of triazine, however, a tetraliedral configuration is produced at tlie zinc... 

Two electron pairs are as far apart as possible when they are directed at 180° to one another. This gives BeF2 a linear structure. The three electron pairs around the boron atom in BF3 are directed toward the comers of an equilateral triangle the bond angles are 120°. We describe this geometry as trigonal planar. 

Whether these results will also have an impact on the theory of metallaallenes is difficult to predict at least for the compounds Cp (CO)2Mn = M = Mn(CO)2Cp, (M = Ge, Sn, Pb) a linear structure is established and also linear p-carbido complexes are known [198], Recently, a germanium compound has been synthesized which is directly comparable with 22. In this case, the starting material for the synthesis is not a monomeric base adduct, but a dimeric germylene complex which is cleaved by Na2Fe(CO)4 in pyridine to form 72 [199],... 

Hexacarbonyldicobalt complexes of alkynes have served as substrates in a variety of olefin metathesis reactions. There are several reasons for complex-ing an alkyne functionality prior to the metathesis step [ 125] (a) the alkyne may chelate the ruthenium center, leading to inhibition of the catalytically active species [125d] (b) the alkyne may participate in the metathesis reaction, giving undesired enyne metathesis products [125f] (c) the linear structure of the alkyne may prevent cyclization reactions due to steric reasons [125a-d] and (d) the hexacarbonylcobalt moiety can be used for further transformations [125c,f]. 

The consensus in the literature is that AOS has rapid biodegradability due to its linear structure, whether assessed on the basis of functional loss or on the basis of loss of organic carbon [2,140]. 

A theoretical study of the m.w.d. broadening during the SPP of a semi-crystaline polymer showed that for linear structures, according to the Schulz-Flory relationship, no narrowing or broadening of the m.w.d. is to be expected (11). 

Each nonpermuted formula is followed by linearized structural formulas that indicate how the elements are combined in groups. They reveal the connectivity of the compounds underlying each empirical formula and serve to distinguish substances which are identical in composition but... 

Each linearized structural formula is followed in a third column by keywords describing the context in which it is discussed and by the numbeKs) of the section(s) in which it occurs. 

Whenever an empirical formula does not show how the elements are combined in groups, it is followed by a linearized structural formula, which reveals the connectivity of the compound(s) underlying the empirical formula and serves to distinguish substances which are identical in composition but differ in the arrangement of elements. The nonpermuted empirical formulas are followed by keywords. They describe the context in which the compounds represented by the empirical formulas are discussed. Section numbers direct the reader to relevant positions in the book. 

The Mg + dicadon [42] with AN+2 (N= 1) valence electrons has a stable structure in agreanent with the rule, but this is a local energy minimum. The linear structure is more stable because it minimizes the Coulomb repulsion. This is in contrast to the tetrahedral stmcture of the Li dication with two electrons (N= 0). The six electron systems caimot form closed-shell structures in the tetrahedron, but the two electron systems can do. 

A priori, a vinyl cation can have two possible geometries a linear structure, 172a, with a sp-hybridized carbon and an empty p orbital or a trigonal form, 172b, with a sp -hybridized carbon and an empty sp orbital. 

Two equivalent ip-hybridized orbitals achieve maximum distance from one another when they arrange in a linear structure ... 

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