AllChemicals — The Online Chemical Glossary | https://allchemicals.info/chemical/357-donor-atom
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Quick Reference
Also Known As
Coordinating atom, binding atom (ligand), Lewis base site, chelating atom
What is Donor Atom?
In coordination chemistry, the atom in a ligand that directly bonds to the central metal atom or ion by donating a lone pair of electrons. Common donor atoms include nitrogen, oxygen, sulfur, and phosphorus. Polydentate ligands have multiple donor atoms.
Properties & Characteristics
A donor atom is the atom within a ligand that directly bonds to the central metal atom in a coordination compound by donating a lone pair of electrons. Common donor atoms include: N (ammonia, amines, pyridine), O (water, carboxylates, DMSO), S (thioethers, thiolates), P (phosphines), C (CO, cyanide, carbenes). The donor atom's identity determines the ligand's hardness/softness and the strength of the metal-ligand bond.
Uses & Applications
Selection of appropriate donor atoms allows tuning of complex stability, reactivity, and selectivity in catalysis, analytical chemistry (chelating agents for specific metal ions), and medicine (EDTA's N and O donors chelate Ca²⁺ and heavy metals in chelation therapy).
Safety Information
Ligands with S donor atoms (thiolates, dithiocarbamates) often show high affinity for heavy metal cations (Hg²⁺, Pb²⁺, Cd²⁺) — both a detoxification principle (chelation therapy) and a source of hazard (displacement of essential metal ions from enzymes).
Always consult the SDS/MSDS before handling any chemical. This information is for educational purposes only.
SynonymsCoordinating atom, binding atom (ligand), Lewis base site, chelating atom
Frequently Asked Questions
In coordination chemistry, the atom in a ligand that directly bonds to the central metal atom or ion by donating a lone pair of electrons. Common donor atoms include nitrogen, oxygen, sulfur, and phosphorus. Polydentate ligands have multiple donor atoms.
Selection of appropriate donor atoms allows tuning of complex stability, reactivity, and selectivity in catalysis, analytical chemistry (chelating agents for specific metal ions), and medicine (EDTA's N and O donors chelate Ca²⁺ and heavy metals in chelation therapy).
Ligands with S donor atoms (thiolates, dithiocarbamates) often show high affinity for heavy metal cations (Hg²⁺, Pb²⁺, Cd²⁺) — both a detoxification principle (chelation therapy) and a source of hazard (displacement of essential metal ions from enzymes).
Editorial standards: Chemical data is sourced from peer-reviewed literature,
CAS Registry, NIST WebBook, and PubChem. Safety information reflects guidance from OSHA, ECHA,
and IAEA. For educational purposes only — always consult official SDS documentation and qualified
professionals before handling chemicals.
