Bond length
The bond length is according to IUPAC definition of the distance between two atomic centers within a chemical bond . The term bond length is defined differently within the scope of various experimental methods, which results in deviations that are generally small.
chemistry
In the case of crystalline solids with an ion or metal grid , the spacing between the grid components can be determined by X-ray or electron diffraction . Since different distances between the lattice planes can be measured in crystal lattices, the smallest distance is usually given as the bond length in tables.
In calcium fluoride , the distance between the calcium cations Ca 2+ and the fluoride anions F - 235 pm (1 pm = 10 −12 m). In metal lattices, the distance is between 200 pm and 500 pm, depending on the atomic size.
For a carbon-carbon bond (single) this distance is approx. 154 pm. For bond lengths of covalent bonds see here . Depending on the degree of polarization, hydrogen bonds have distances between 120 pm and 300 pm.
Bond lengths in organic compounds C-H Length in pm C-C Length in pm Multiple bonds Length in pm sp 3 -H 110 sp 3 - sp 3 154 benzene 140 sp 2 -H 109 sp 3 - sp 2 150 Alkene (C = C) 134 sp-H 108 sp 2 -sp 2 147 Alkyne (C≡C) 120 sp 3 - sp 146 sp 2 - sp 143 sp - sp 137
Further bond lengths of covalent bonds
binding Bond length in pm HH 74 FF 142 Cl-Cl 199 Br-Br 228 II 267 O = O 121 N≡N 110 NH 101 OH 96 FH 92 Cl-H 127 Br-H 141 IH 161 CO 143 C = O 120 CN 147 C (sp) -Li 188-193 C (sp) -Na 222 C (sp) -K 254
Individual evidence
- ^ A b International Union of Pure and Applied Chemistry: IUPAC Gold Book - bond length. Retrieved January 20, 2019 .
- ^ Norman L. Allinger: Molecular Structure . Wiley, 2010, ISBN 978-0-470-19557-4 , doi : 10.1002 / 9780470608852 ( wiley.com [accessed January 20, 2019]).
- ^ Marye A. Fox, James K. Whitesell: Organic Chemistry . Spektrum Akademischer Verlag, 1995, ISBN 3-86025-249-6 .
- ↑ a b c Grotjahn DB; Apponi, AJ; Brewster, MA; Ju Xin; Ziurys LM Angew. Chem. 1998 , 110 (19) , 2824-2827.