ion

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ion

 [i´on]
an atom or group of atoms having a positive (cation) or negative (anion) electric charge by virtue of having gained or lost an electron; substances forming ions are called electrolytes. adj., adj ion´ic.
dipolar ion an ion that has both positive and negative regions of charge.
hydrogen ion the positively charged hydrogen atom (H+), which is the positive ion of all acids. See also hydrogen ion concentration.
hydroxyl ion the negatively charged group, OH, present to excess in alkaline solutions.

i·on

(ī'on),
An atom or group of atoms carrying an electric charge by virtue of having gained or lost one or more electrons. Ions charged with negative electricity (anions) travel toward a positive pole (anode); those charged with positive electricity (cations) travel toward a negative pole (cathode). Ions may exist in solid, liquid, or gaseous environments, although those in liquid (electrolytes) are more common and familiar.
[G. iōn, going]

i·on

(ī'on)
An atom or group of atoms carrying an electric charge by virtue of having gained or lost one or more electrons. Ions charged with negative electricity (anions) travel toward a positive pole (anode); those charged with positive electricity (cations) travel toward a negative pole (cathode). Ions may exist in solid, liquid, or gaseous environments, although those in liquid (electrolytes) are more common and familiar.
[G. iōn, going]

ion

An electrically charged atom, group of atoms, or molecule. A positive ion is an atom that has lost an electron; a negatively charged ion is one that has gained an electron. See also IONIZATION.

ion

an atom that carries a charge due to loss or gain of electrons.

Ion

An atom or group of atoms that acquires an electrical charge by the gain or loss of electrons.

ion

(ī'on)
An atom or group of atoms carrying an electric charge by virtue of having gained or lost one or more electrons. Ions charged with negative electricity (anions) travel toward a positive pole (anode); those charged with positive electricity (cations) travel toward a negative pole (cathode). Ions may exist in solid, liquid, or gaseous environments, although those in liquid (electrolytes) are more common and familiar.
[G. iōn, going]
References in periodicals archive ?
Even when the unsubstituted molecules are unstable, their dianions and several substituted derivatives stabilize both sterically and electronically, resulting in thermally stable structures at room temperature [2].
Generation of dianion (base) in the presence of phosphonium salt and concomitant formation of ylide at sufficiently high cathodic potential as per Eq.
Since two fluorescein species exist in PBS with different quantum yields and only the fluorescein dianion is present in borate buffer solution, MESF values can not be assigned to microbeads suspended in PBS using the calibration curve made by a series of dilutions of Fluorescein Solution SRM in borate buffer.
All the observed vibrational frequencies and the general pattern of these spectra [35-42] are in agreement with the semiempirical QCFF/PI [44] and DFT theoretical calculations for [C.sub.76]-[D.sub.2] [45], as well as for its dianion [C.sub.76]-[D.sub.2.sup.2-] [45].
It has been demonstrated [20] that selective functionalization of 47-hydroxyl group in genistein requires initial double deprotonation with a strong base because resulting dianion exhibits different nucleophilicity at both phenolate centers, favoring preferred direction of O-alkylation.
Previous studies [29, 30] showed that, at acidic pH and neutral pH, there were two reduction peaks, one reversible two-electron reduction of the quinone unit of doxorubicin hydrochloride to quinone dianion species at -600 mV (versus calomel electrode), that is, -644 mV (versus Ag/AgCl, saturated KCl), and another irreversible peak at much more negative potential owing to hydrogen evolution [31].
The asymmetric and symmetric stretching frequencies of the carboxylate ions are seen at 1613 and 1410 [cm.sup.-1], respectively with the [DELTA][upsilon] (uasymm-usym) separation of 203 [cm.sup.-1], which indicate the monodentate linkage of both carboxylate groups in the dianion. The N-H stretching is observed at 3029 [cm.sup.-1].
Hydrolysis rates were measured at 415 nm for 3 min with 30 s intervals, monitored by the formation of the thiolate dianion of DTNB.
(1988) Preparation and reactions of 1,1,4,4-tetrakis(trimethylsilyl)butane-1,4-diyl dianion. Tetrahedron Lett.
9:30 Condensation-Cyclization of Polylithiated Methyl (2-Aminosulfonyl)benzoate with Several Dianion Type Intermediates.
Naz, Kinetics studies of hydrogen bonding in quinone anion radical and the dianion of tetramethyl-1, 4-benzoquinone, J.Chem.
Preferential binding of the dianion and pH effects," Journal of Physical Chemistry B, vol.