Bond lengths carbon-bromine

Figure 8.B The carbon-bromine bond length (shown in angstroms) at the central carbon increases as less electron density from the bromine is needed to stabilize the positive charge. A lesser electron density contribution from bromine is needed because additional alkyl groups help stabilize the charge...

Figure 9-6 Bond lengths, angles, and arrangement of carbons and bromines in a crystal of 1,8-bis(bromomethyl)naphthalene, 1, as determined by x-ray diffraction. Notice that the preferred conformation in the crystal has the bromines on opposite sides of the naphthalene ring.

Carbon-bromine bond distances in some bromoacetylenes are listed in Table 39. The bond lengths are nearly constant at about 179 pm and possible variations due to different substituents at the opposite carbon atom are smaller than the experimental uncertainties and systematic differences between the different types of bond lengths. The rs value for the C—Br bond distance in the cyano compound [178.9(2) pm] is equal to the value derived for acetylene [179.16(30) pm]. Shortening of the bond by ca 4 pm occurs in the electronic ground state of the bromine cyanide cation. 

Here, the initial carbon-bromine distance is 3.6 A, compared to an equilibrium C—Br bond length of 1.97 A in bromoformic acid [143]. 

PRACTICE EXAMPLE A Estimate the bond lengths of the carbon-to-hydrogen bonds and the carbon-to-bromine bond in CH3Br. 

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