INDEX Single bond

This group of compounds includes those monomers with one or more carbon atoms carrying a hydroperoxy or peroxy group, and also singly bonded to an oxygen atom present as hydroxyl, ether or cyclic ether functions. While the group of compounds is, in general, moderately stable, the lower 1-hydroxy and 1,T-dihydroxy-alkyl peroxides or hydroperoxides are explosive. Individually indexed compounds are ... 

The sydnones may be represented by structures (160a-d), of which the zwitterionic structures (160a,b) most clearly imply an aromatic sextet. p-Bromophenylsydnone (160 R-H, R -p-bromophenyl) is essentially planar. However, the O—N bond and 0(1)—C(5) bond lengths are not very different from normal single bond distances. Contributions of structures (160c,d) to the resonance hybrid are important, and the structural index of sydnone reveals its a rather low aromaticity (AN= 17%). 

There are a number of compounds containing N—O single bonds which are of limited or low stability. As well as the groups below there are the individually indexed compounds ... 

There will be numerous facts to learn in the course of the year, however. For example, chemical reagents necessary to carry out specific reactions must be learned. You might find a study aid known as flash cards helpful. These take many forms, but one idea is to use 3X5 index cards. As an example of how the cards might be used, consider the reduction of alkenes (compounds with carbon-carbon double bonds) to alkanes (compounds containing only carbon-carbon single bonds). The front of the card might look like this ... 

Bond order A theoretical index of the degree of bonding between two atoms relative to that for a normal single bond, that is, one localized electron pair. In valence bond theory it is expressed by the weighted average of the bond numbers between the respective atoms in the contributing structures. By this criterion each C—C bond in benzene has a bond order of 1.5. 

Moreover, the composite reference ETA index, denoted as tir, is calculated as the composite ETA index from a molecular graph where all heteroatoms are substituted by carbon atoms and all the multiple bonds by single bonds. Then, the functionality index Tip is defined as the difference between the composite reference ETA index and the composite ETA index ... 

The correlation coefficient between o(exp) and BB I (the second most important index) is 0.7980. The ease of rotational or oscillational motions around a backbone bond emanating from an atom which is singly bonded to all of its neighbors increases with decreasing (8/8v), as is shown in Figure 12.5 for the first-row atoms C, N and O in bonding environments in which... 

In the United States, Canada, and New Zealand, indexed bonds can be stripped, allowing coupon and principal cash flows to be traded separately. This obviates the need for specific issues of zero-coupon indexed securities, since the market can create products such as deferred-payment indexed bonds in response to specific investor demand. In markets allowing stripping of indexed government bonds, a strip is simply a single cash flow with an inflation adjustment. An exception to this is in New Zealand, where the cash flows are separated into three components the principal, the principal inflation adjustment, and the inflation-linked coupons—the latter being an indexed annuity. 

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