Bond distance, also

II, A this suggests that, in this molecule at least, fluorine is functioning as a weak 7r-donor. The measured C—F bond distances also support this idea. 

Deuterium sites for Sr2IrDs and Sr2RuDg were located from neutron diffraction studies, and the positions that gave the best fit (24) are summarized in Table II. With these coordinates, bond distances also were determined and are shown in Table III. The transition elements were viewed as six coordinate with respect to deuterium, where the atomic ratios were D Ru = 6 for Sr2RuDe and D Ir = 5 plus one random vacancy for Sr2IrDs. 

This reaction is accompanied by changes in the infrared spectrum in the CO region, as listed above. The Mo—Mo bond distance also shortens by approximately 100 pm, consistent with an increase in the metal-metal bond order from 1 to 3. Although it was originally proposed that the linear CO ligands may donate some electron density to the neighboring metal from tt orbitals, subsequent calculations have indicated that a more important interaction is donation from a metal d orbital to... 

Measured C—O bond distances also reflect the importance of electron delocalization in acetate ion. Acetic acid s bond distances are consistent with a short double bond (121 pm) and a long single bond (136 pm), whereas the two carbon-oxygen bond distances... 

D(M—CO) increases across the First Transition Series from Cr to Ni (except for Mn), and down Group VI (Cr < Mo < W). The increase in M—C bond strength down a transition metal group contrasts with the decrease down a group which is generally observed with main group elements (p. 5). M—CO bond distances also decrease across a transition series, following the contraction in covalent radius of the metal. 

At Its most basic level separating the total strain of a structure into its components is a qualita tive exercise For example a computer drawn model of the eclipsed conformation of butane using ideal bond angles and bond distances (Figure 3 8) reveals that two pairs of hydrogens are separated by a distance of only 175 pm a value considerably smaller than the sum of their van der Waals radii (2 X 120 pm = 240 pm) Thus this conformation is destabilized not only by the torsional strain associ ated with its eclipsed bonds but also by van der Waals strain... 

Because the carbons that are singly bonded m one resonance form are doubly bonded m the other the resonance description is consistent with the observed carbon-carbon bond distances m benzene These distances not only are all identical but also are intermediate between typical single bond and double bond lengths... 

As expected, the Sb—Sb bond distance in this complex is significandy shoitei than the Sb—Sb single bond distance. Chioinium and tungsten complexes of dialkyldistibines have also been isolated (132). 

Solid state NMR is a relatively recent spectroscopic technique that can be used to uniquely identify and quantitate crystalline phases in bulk materials and at surfaces and interfaces. While NMR resembles X-ray diffraction in this capacity, it has the additional advantage of being element-selective and inherently quantitative. Since the signal observed is a direct reflection of the local environment of the element under smdy, NMR can also provide structural insights on a molecularlevel. Thus, information about coordination numbers, local symmetry, and internuclear bond distances is readily available. This feature is particularly usefrd in the structural analysis of highly disordered, amorphous, and compositionally complex systems, where diffraction techniques and other spectroscopies (IR, Raman, EXAFS) often fail. 

The S-N bond in [SO2N3] is much weaker than that in [SO3N3] as reflected in an increase in the S-N bond distance by 0.23 A in the Cs " salts.The S-N bond length in [Me4N][S02N3] is 2.00 A. " This marked difference can be attributed to the much weaker Lewis acidity of SO2 compared to that of SO3 which also results in lower thermal stability for the [SO2N3] anion. 

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