Bond lengths carbon-chlorine

Figure 5. Carbon-chlorine bond lengths (A) of chlorinated dibenzo-p-dioxins as a function of the number of chlorine substituents.

Pale-yellow (NSC1)3 may be recrystahised from carbon tetrachloride without decomposition when the temperature is kept below 50 °C. In the solid state, the six-membered ring adopts a chair conformation with ah three chlorine atoms in axial positions and equal S-N bond lengths ca 1.60 A). This arrangement is stabilised by the anomeric eifect (delocalisation of the nitrogen lone pair into an S-Cl c orbital). ... 

Ans. The predicted bond length is 141 pm however, the presence of the C=C and the chlorine will tend to affect this prediction. Fluorine and chlorine are quite electronegative (compared with carbon), forming negative centers that tend to repel. 

C(sp)—Cl bond distances in various acetylenes (Table 28) have a remarkably constant value of ca 163.5 pm and variations due to electron-donating (Me, t-Bu, SiH3) or electron-withdrawing substituents (F, Cl, CN) at the opposite carbon are smaller than the experimental uncertainties. ED and MW for chlorobromoacetylene result in rather different ra and r0 values for the C—Cl bond length and this discrepancy may be due to large-amplitude bending vibration of this linear molecule. A similar, but smaller difference between ra and rs values occurs for chlorocyanoacetylene. The rs value for chlorine cyanide is also in line with the results for the acetylenes. 

The single bond covalent radius of carbon may be taken to be about 0.77 A, just half of the C—C bond length in diamond. Similarly, the covalent radii of chlorine and iodine may be set at 0.99 A and 1.33 A, respectively, one half of the interatomic distances in the Ch and I2 molecules. 

The Ge atom in 154 is pentacoordinated due to intramolecular N —Ge coordination and it has a distorted TBP arrangement at the germanium center, with three equatorial carbon atoms and axial chlorine and nitrogen. The axial bond lengths (Table 36) are significantly longer than the sum of the covalent radii for these elements (Table 1). 

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