ligandn.

Brit.

/ˈlɪɡ(ə)nd/, U.S.

/ˈlɪɡənd/,

/ˈlaɪɡənd/

Etymology: < Latin ligandus, gerundive of ligāre to bind.

Chemistry.

Each of the atoms or groups attached to the central (usually the metal) atom of a co-ordination complex.

ΘΚΠ

the world > matter > chemistry > atomic chemistry > [noun] > ligands

ligand1952

1952 Jrnl. Chem. Soc. 4757 Inferences from spectral absorption to thermochemical stability are therefore very speculative, particularly if different types of ligand, say ions and neutral dipoles, are being compared.

1964 J. W. Linnett Electronic Struct. Molecules viii. 138 This implies that..the tendency to form a multiple bond is about the same for the PF₃ ligand as for CO.

1964 Oceanogr. & Marine Biol. 2 250 The relative accumulation factors for metals in marine organisms are related, in general, to the stability of the metal ions with ligands.

1971 Arch. Biochem. & Biophysics 147 226/1 At each monomer active site the two iron atoms can be bridged by two small, inorganic ligands.

Compounds

ligand exchange n. exchange of ligands between complexes.

ΘΚΠ

the world > matter > chemistry > atomic chemistry > [noun] > ligands > exchange of

ligand exchange1964

1964 Jrnl. Amer. Chem. Soc. 86 765 (heading) Rates of rapid ligand exchange reactions by nuclear magnetic resonance line broadening studies.

1973 Jrnl. Chromatogr. 87 513 A rapid ligand-exchange chromatographic method for the separation of α-amino acids from peptides is presented.

ligand field n. the electrostatic field produced by the ligands in the vicinity of the central atom; so ligand field theory, the branch of chemical theory which deals with the effect of ligands on the energy levels of the central atom or ion; spec. a theory based on an electrostatic model modified by molecular orbital considerations.

ΘΚΠ

the world > matter > chemistry > atomic chemistry > [noun] > ligands > theory of

ligand field theory1956

the world > matter > physics > atomic physics > particle physics > particle avoiding strong interaction > electron > [noun] > electrostatic field

ligand field1956

1956 Nature 18 Feb. 305/2 A proper consideration of the effect of the ligand~field explains why the six-coordinate complexes of nickel are equally stable with the cupric complexes.

1960 L. Pauling Nature Chem. Bond (ed. 3) v. 174 In some respects the ligand field theory is closely related..to the valence bond theory.

1966 F. A. Cotton & G. Wilkinson Adv. Inorg. Chem. (ed. 2) xxvi. 661 This modified CFT [sc. crystal field theory] is often called ligand field theory, LFT. However, LFT is sometimes also used as a general name for the whole gradation of theories from the electrostatic CFT to the MO [sc. molecular orbital] formulation.

1970 W. L. Jolly Synthesis & Characterization Inorg. Compounds xxii. 324 If we were able gradually to decrease the ligand field strength to zero, we would find that each term would gradually approach an energy corresponding to one of the states of the free ion.

1971 Orchin & Jaffé Symmetry, Orbitals & Spectra vii. 170 Interpretation of the spectra of inorganic complexes is greatly simplified and successfully integrated by the use of ligand field theory.

Derivatives

ˈligancy n. = co-ordination number at co-ordination n. 5.

ΚΠ

1960 L. Pauling Nature Chem. Bond (ed. 3) ii. 63 A sharp distinction is to be made between the number of atoms bonded to a central atom (the ligancy or coordination number of the central atom) and the number of covalent bonds formed by the central atom (its covalence).

1960 L. Pauling Nature Chem. Bond (ed. 3) xiii. 538 The changes from the standard sodium chloride and rutile arrangements, with ligancy 6, to cesium chloride and fluorite, respectively, with ligancy 8, are nearly the same.

1965 C. S. G. Phillips & R. J. P. Williams Inorg. Chem. I. v. 157 The presence of shared edges and especially of shared faces in a coordinated structure decreases its stability; this effect is large for cations with large valence and small ligancy.

1968 Inorg. Chem. VII. 1945/2 There are certain bonding situations common in boron chemistry and uncommon elsewhere that lead to unusual nomenclature problems. These include..excess connectivity or ligancy.

ˈliganded adj. bound to a ligand or ligands.

ΘΚΠ

the world > matter > chemistry > atomic chemistry > [adjective] > relating to ligards > bound to a ligard

liganded1967

1967 Jrnl. Biol. Chem. 242 3705/2 If the αβ dimer that reacts with ligand is free in solution, the now liganded dimer, α*β*, can associate with another liganded dimer to produce a liganded tetramer, α₂*β₂*.

1973 Jrnl. Molecular Biol. 76 238 Hybrids formed in a mixture of HbS and CN met-Hb A would, upon deoxygenation, contain one liganded α chain and one liganded β chain.

Draft additions 1997

ΘΚΠ

the world > matter > chemistry > chemical bonding > [noun] > ligand

ligand1938

1938 Bull. Chem. Soc. Japan 13 388 In more special cases, selective absorption bands due to ligands themselves may superpose on those proper to the co-ordination combination. [Note] Throughout this article, the word ligand will be used in its original German sense, i.e., an ion or a molecule co-ordinated in a complex radical.

1948 Nature 6 Nov. 746/1 It is seen that the stability of complexes increases steadily to reach a maximum at copper whether the ligands be ammonia, ethylene diammine, propylene diammine or salicylaldehyde.

b. Immunology. A molecule or group which binds to another molecule (usually a macromolecule) with a high degree of specificity.

ΚΠ

1968 B. Belleau in E. J. Ariëns Physico-Chem. Aspects Drug Action 207 A fundamental study of the interaction mechanisms of ligands (or small molecules) with macromolecules.

1971 Proc. National Acad. Sci. U.S.A. 68 1047/1 Acting on the hypothesis that in vitro, ACh receptor retains its affinity for cholinergic ligands and binds them reversibly and competitively, we searched for such macromolecules in different excitable tissues.

1978 Res. in Reproduction May 2/1 Increasing quantities of serum in particular tubes yields dose-related inhibition of binding of the ligand to the antibody or receptor.

1989 B. Alberts et al. Molecular Biol. Cell (ed. 2) vi. 325 Mast cells secrete histamine..when triggered by specific ligands that bind to receptors on their surface.

This entry has not yet been fully updated (first published 1976; most recently modified version published online March 2022).

单词	ligand
释义	ligandn. Brit. /ˈlɪɡ(ə)nd/, U.S. /ˈlɪɡənd/, /ˈlaɪɡənd/ Etymology: < Latin ligandus, gerundive of ligāre to bind. Chemistry. Each of the atoms or groups attached to the central (usually the metal) atom of a co-ordination complex. ΘΚΠ the world > matter > chemistry > atomic chemistry > [noun] > ligands ligand1952 1952 Jrnl. Chem. Soc. 4757 Inferences from spectral absorption to thermochemical stability are therefore very speculative, particularly if different types of ligand, say ions and neutral dipoles, are being compared. 1964 J. W. Linnett Electronic Struct. Molecules viii. 138 This implies that..the tendency to form a multiple bond is about the same for the PF₃ ligand as for CO. 1964 Oceanogr. & Marine Biol. 2 250 The relative accumulation factors for metals in marine organisms are related, in general, to the stability of the metal ions with ligands. 1971 Arch. Biochem. & Biophysics 147 226/1 At each monomer active site the two iron atoms can be bridged by two small, inorganic ligands. Compounds ligand exchange n. exchange of ligands between complexes. ΘΚΠ the world > matter > chemistry > atomic chemistry > [noun] > ligands > exchange of ligand exchange1964 1964 Jrnl. Amer. Chem. Soc. 86 765 (heading) Rates of rapid ligand exchange reactions by nuclear magnetic resonance line broadening studies. 1973 Jrnl. Chromatogr. 87 513 A rapid ligand-exchange chromatographic method for the separation of α-amino acids from peptides is presented. ligand field n. the electrostatic field produced by the ligands in the vicinity of the central atom; so ligand field theory, the branch of chemical theory which deals with the effect of ligands on the energy levels of the central atom or ion; spec. a theory based on an electrostatic model modified by molecular orbital considerations. ΘΚΠ the world > matter > chemistry > atomic chemistry > [noun] > ligands > theory of ligand field theory1956 the world > matter > physics > atomic physics > particle physics > particle avoiding strong interaction > electron > [noun] > electrostatic field ligand field1956 1956 Nature 18 Feb. 305/2 A proper consideration of the effect of the ligand~field explains why the six-coordinate complexes of nickel are equally stable with the cupric complexes. 1960 L. Pauling Nature Chem. Bond (ed. 3) v. 174 In some respects the ligand field theory is closely related..to the valence bond theory. 1966 F. A. Cotton & G. Wilkinson Adv. Inorg. Chem. (ed. 2) xxvi. 661 This modified CFT [sc. crystal field theory] is often called ligand field theory, LFT. However, LFT is sometimes also used as a general name for the whole gradation of theories from the electrostatic CFT to the MO [sc. molecular orbital] formulation. 1970 W. L. Jolly Synthesis & Characterization Inorg. Compounds xxii. 324 If we were able gradually to decrease the ligand field strength to zero, we would find that each term would gradually approach an energy corresponding to one of the states of the free ion. 1971 Orchin & Jaffé Symmetry, Orbitals & Spectra vii. 170 Interpretation of the spectra of inorganic complexes is greatly simplified and successfully integrated by the use of ligand field theory. Derivatives ˈligancy n. = co-ordination number at co-ordination n. 5. ΚΠ 1960 L. Pauling Nature Chem. Bond (ed. 3) ii. 63 A sharp distinction is to be made between the number of atoms bonded to a central atom (the ligancy or coordination number of the central atom) and the number of covalent bonds formed by the central atom (its covalence). 1960 L. Pauling Nature Chem. Bond (ed. 3) xiii. 538 The changes from the standard sodium chloride and rutile arrangements, with ligancy 6, to cesium chloride and fluorite, respectively, with ligancy 8, are nearly the same. 1965 C. S. G. Phillips & R. J. P. Williams Inorg. Chem. I. v. 157 The presence of shared edges and especially of shared faces in a coordinated structure decreases its stability; this effect is large for cations with large valence and small ligancy. 1968 Inorg. Chem. VII. 1945/2 There are certain bonding situations common in boron chemistry and uncommon elsewhere that lead to unusual nomenclature problems. These include..excess connectivity or ligancy. ˈliganded adj. bound to a ligand or ligands. ΘΚΠ the world > matter > chemistry > atomic chemistry > [adjective] > relating to ligards > bound to a ligard liganded1967 1967 Jrnl. Biol. Chem. 242 3705/2 If the αβ dimer that reacts with ligand is free in solution, the now liganded dimer, αβ, can associate with another liganded dimer to produce a liganded tetramer, α₂β₂. 1973 Jrnl. Molecular Biol. 76 238 Hybrids formed in a mixture of HbS and CN met-Hb A would, upon deoxygenation, contain one liganded α chain and one liganded β chain. Draft additions 1997 a. ΘΚΠ the world > matter > chemistry > chemical bonding > [noun] > ligand ligand1938 1938 Bull. Chem. Soc. Japan 13 388 In more special cases, selective absorption bands due to ligands themselves may superpose on those proper to the co-ordination combination. [Note] Throughout this article, the word ligand will be used in its original German sense, i.e., an ion or a molecule co-ordinated in a complex radical. 1948 Nature 6 Nov. 746/1 It is seen that the stability of complexes increases steadily to reach a maximum at copper whether the ligands be ammonia, ethylene diammine, propylene diammine or salicylaldehyde. b. Immunology. A molecule or group which binds to another molecule (usually a macromolecule) with a high degree of specificity. ΚΠ 1968 B. Belleau in E. J. Ariëns Physico-Chem. Aspects Drug Action 207 A fundamental study of the interaction mechanisms of ligands (or small molecules) with macromolecules. 1971 Proc. National Acad. Sci. U.S.A. 68 1047/1 Acting on the hypothesis that in vitro, ACh receptor retains its affinity for cholinergic ligands and binds them reversibly and competitively, we searched for such macromolecules in different excitable tissues. 1978 Res. in Reproduction May 2/1 Increasing quantities of serum in particular tubes yields dose-related inhibition of binding of the ligand to the antibody or receptor. 1989 B. Alberts et al. Molecular Biol. Cell (ed. 2) vi. 325 Mast cells secrete histamine..when triggered by specific ligands that bind to receptors on their surface. This entry has not yet been fully updated (first published 1976; most recently modified version published online March 2022). < n.1938
随便看	to give the wrong to to give their cards to give thing) the fingers to give third point to give time to give to a person on a plate to give to believe, know, note, understand to give to drink to give to eat to give to keep to give to lot to give to lot to to give to marriage to give to on a plate to give to one's fere to give to pledge to give to rede to give to reflect to give to suck to give to the public to give to the world to give to think to give to warison to give to wife to give tongue