Length, observation

Fig. 42.8. Autocorrelograms of the queue lengths observed in a department for structural analysis.

Figure 5. A schematic model for the structure in TEOS-PTMO hybrid systems, (A) PTMO chain, (B) linear species based on partially condensed TEOS, (C) cluster formed by highly condensed TEOS. 1/s corresponds to the correlation length observed in SAXS profiles.

It should be noted that all the M=X bond lengths observed here are significantly shorter than those reported for the corresponding double bond compounds stabilized by intramolecular coordination of heteroatoms. In other words,... 

Limited theoretical studies (31, 89) on the electron-deficient beryllium derivatives have been interpreted to imply that extensive Be—Be bonding occurs. If such bonding does occur, the increased bond length observed in the phenylethynyl(methyl)beryllium trimethylamine adduct takes on additional significance since the Be—Be distance in this derivative is increased by almost 0.3 A over that observed in dimethyl-and diethylberyllium. Moreover, if cyclic trimers are formed, then increased metal-metal distances would be likely, thus reducing the probability of stabilization of the bridged system by Be—Be bonding. Additional studies will be required both on structures and of spectroscopic properties of the species to answer these questions. 

The answers to these questions and other questions about the transition-metal complexes have been provided by a new idea about their structure, developed in 1935 to account for the bond lengths observed in the nickel tetracarbonyl molecule. This idea is that atoms of the transition groups are not restricted to the formation of single covalent bonds, but can form multiple covalent bonds with electron-accepting ligands by making use of the 3d (or 4d, 5d) orbitals and electrons of the transition metal. 

The coverage time for each wavy solid layer multiplied by the descending velocity gives the characteristic length of the wavy solids layer. Jiang et al. (1993) reported that the most probable length observed is around 20 cm. 

Substance Bond Predicted Length Observed Length... 

The diaminodisilyldisilene 8 has a most unusual structure it not only exhibits the longest Si=Si formal double bond length observed to date but also the largest tram-bent and twist angles. These structural parameters are probably attributable to the substitution patterns in 8. Although the Si—Si bond in the intermediate 7 promotes the formation of an Si=Si double bond, the Si—N bond also present hinders electronically Si—Si contacts, with the overall result that the structural parameters described above represent a compromise between these opposing effects28. It is important to note that theoretical calculations fully reproduce the experimentally determined structure of 827. 

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