Bonding radii

Element Single-bond radius, pm Double-bond radius, pm Triple-bond radius, pm... 

Fig. 5.—The dependence of single-bond radius on the number of bonding d orbitals.

Because of the occasional occurrence of a difference in hybridization of the bond orbitals involved in bonds of different classes, leading to a difference in single-bond radius, the determination of the bond numbers from experimental values of the bond lengths involves some uncertainty. 

This system is based on the observations (Pauling 1947) that a linear relation between single-bond radius and atomic number holds for bonds of constant hybrid character, and that for an element the single-bond radius is (at least approximately) linearly dependent on the d character of the dsp hybrid bond orbitals. 

The values of iJ sp3), the single-bond radius for sp3 bonds, for the iron-transition elements are given by the equation... 

Also, for some elementary metals, such as with the A2 structure (cubic body-centered), there has been uncertainty about how to divide the total valence of the atom between the non-equivalent bonds, and consequent uncertainty in the value of the single-bond radius of the metal. 

A way to overcome some of these difficulties can be developed on the assumption that in metals and intermetallic compounds the nonequivalent bond orbitals in an atom may have different hybrid character, such as to correspond to suitable values of R, the single-bond radius of the atom. A set of empirical equations giving the single-bond radius as a function... 

In the course of the work it was found that the value assumed five years ago for the carbon double-bond covalent radius (obtained by linear interpolation between the single-bond and the triple-bond radius) is 0.02 A. too large in consequence of this we have been led to revise the double-bond radii of other atoms also. 

There is little doubt that the C-C distance in the benzene ring retains in its methyl derivatives the value 1.39 A. found for benzene itself.19 The main question regarding these substances is whether the distance from methyl carbon to ring carbon is determined by the usual single-bond radius, having thus the value 1.54 A., or whether... 

It has been found that a carbon-oxygen double bond decreases the single-bond radius of the carbon atom involved Pauling and Brockway, paper to be submitted to This Journal. 

Revised Values of Double-Bond Covalent Radii.—This investigation has led to the value 1.34 A. for the carbon-carbon double-bond distance, 0.04 A. less than the value provided by the table of covalent radii.111 4 Five years ago, when this table was extended to multiple bonds, there were few reliable experimental data on which the selected values for double-bond and triple-bond radii could be based. The single-bond radii were obtained -from the study of a large number of interatomic distances found experimentally by crystal-structure and spectroscopic methods. The spectroscopic value of the triple-bond radius of nitrogen (in N2) was found to bear the ratio 0.79 to the single-bond radius, and this ratio was as-... 

The position of the bond critical point. The distance of this point from each of the nuclei is a measure of the size of each atom, that is, its bonding radius rb. 

The bonding radius of A in a diatomic hydride AH at first decreases across a period and then increases because there is a competition between two opposing effects ... 

The nuclear charge increases across the period, which decrease the size of the atom and therefore its bonding radius. 

On the left of the period, effect 1 predominates, while on the right effect 2 predominates, so that overall the bonding radius at first decreases and then increases again. However, the bond length R decreases across the period because of the large decrease in the bonding radius of hydrogen. 

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