| 释义 |
covalency Chem.|kəʊˈveɪlənsɪ|
[f. co- 3 a + valency.]
a. The linking of two atoms by a bond in which they ‘share’ a pair of electrons; a covalent bond.
b. The number of electrons in an atom that go to form a covalent bond; the number of covalent bonds that an atom can form.
1919I. Langmuir in Proc. Nat. Acad. Sci. V. 255 The covalency of an element according to the Octet Theory can never exceed four, since there are only four pairs of electrons in an octet. 1946Jrnl. R. Aeronaut. Soc. L. 392 A tendency towards covalency formation in place of the ionic bond (e.g., the formation of a volatile chloride which is non-ionised in the solid state). 1950N. V. Sidgwick Chem. Elements I. p. xvii, The maximum value of the covalency is limited..in accordance with the period of the atom in the table. 1964N. G. Clark Mod. Org. Chem. ii. 24 There is a second mode of covalency formation..in which both the electrons of the resulting valency bond are provided by one of the atoms. |