Bond parameters double

In some respects, our sample of molecules is not sufficiently representative for building a set of additivity parameters, having a strong bias towards small molecules, where we would expect special bonding situations—double bonds, for instance—to dominate the magnetizability to a greater extent than in larger molecules. If instead we restrict ourselves to the study of a... 

BOND PARAMETERS AFFECTING FAILURE OF CO-CURED SINGLE AND DOUBLE LAP JOINTS SUBJECTED TO STATIC AND DYNAMIC TENSILE LOADS... 

Bond Parameters Affecting Failure of Co-Cured Single and Double Ixtp Joints... 

Acetoxylation of alkenes takes place in allylic position [40,115], concurrent with addition of acetoxy groups across the double bond or double-bond system. The mechanism is almost certainly analogous to that discussed previously for methoxylation [Eq. (20)]. Because AcO is difficult to oxidize, the anodic discharge of simple, unactivated alkenes may be achieved in its presence. Subsequent reactions of the cationic intermediates are not very selective, but several experimental parameters may be controlled and the method can compare well with the few competing chemical methods. 

Letcher and Van Wazer applying LCAO theory first developed by Pople and Karplus and Das, have expressed the shielding (which was dominated by the magnitude of (7 ), in terms of localized bond parameters, e.g., ionic character, hybridization and double bonding. Using expressions for (7 obtained by Jameson and Gutowsky and taking account of both phosphorus p and d orbital occupation, the phosphorus chemical shift, <5 —was related to four parameters and/by equation (11)—... 

Table 5 Structural parameters of heavy ketones Tbt(R)M=Ch. d lengths of an M=Ch double bond, EZM summation of the bond angles around M atom, Aobs percent reduction in bond lengths defined as [(single-bond lengths - double-bond length)/single-bond lengths] xlOO)...

The bond parameters of 2H-pyran-2-one (1 earlier nomenclature a-pyrone, 2-pyrone), as determined by microwave spectroscopy, correspond to an enol-lactone structure with alternately localized C-C double and single bonds, as shown in Figure 6.3 ... 

It seems now established by NMR spectroscopic investigations that a change can take place in electronic structures and atomic configuration of the dyes depending on the polarity of the solvent. Parameters describing the transition from one single bond to more double bond character vary according to the nature of the solvent (107). 

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