Search research articles

ABOUT JoVE

Overview Leadership Blog JoVE Help Center

AUTHORS

Publishing Process Editorial Board Scope & Policies Peer Review FAQ Submit

LIBRARIANS

Testimonials Subscriptions Access Resources Library Advisory Board FAQ

RESEARCH

JoVE Journal Methods Collections JoVE Encyclopedia of Experiments Archive

EDUCATION

JoVE Core JoVE Business JoVE Science Education JoVE Lab Manual Faculty Resource Center Faculty Site

Terms & Conditions of Use

Related Concept Videos

Complexometric Titration: Ligands

Complexometric Titration: Ligands

Different monodentate and polydentate ligands are used as complexing agents in complexometric titration reactions. The formation of complexes by mono- and bidentate ligands involves two or more intermediate steps, limiting their use as complexing agents. In comparison, polydentate ligands can form complexes with metal ions in a single-step process, facilitating sharper end points. This means polydentate ligands, such as amino carboxylic acid derivatives, are most commonly employed in...

EDTA: Chemistry and Properties

EDTA: Chemistry and Properties

Polydentate ligands are most widely used in complexometric titrations because they form more stable complexes with the metal ions than mono- or bidentate ligands due to the chelate effect. Examples of polydentate ligands are ethylenediaminetetraacetic acid (EDTA), crown ethers, and cryptands. The most important feature of optimal polydentate ligands is the ability to form 1:1 complexes in a single-step process. Amino carboxylic acid derivatives are frequently used as complexing agents. EDTA is...

Complexation Equilibria: The Chelate Effect

Complexation Equilibria: The Chelate Effect

In complexation reactions, metal atoms or cations interact with ligands to form donor-acceptor adducts called metal complexes. Ligands that bind through one donor site are monodentate, ligands with two donor sites are bidentate, and those with more than two donor sites are polydentate ligands. For example, ethylene diamine is a bidentate ligand that binds through two nitrogen donor atoms, forming a five-membered ring. EDTA is a polydentate ligand that binds through four oxygen and two nitrogen...

EDTA: Auxiliary Complexing Reagents

EDTA: Auxiliary Complexing Reagents

EDTA titrations are usually carried out in highly basic conditions, where the fully deprotonated form of EDTA, Y4−, actively complexes with the free metal ions in the solution. Several metal ions precipitate as hydrous oxide (hydroxides, oxides, or oxyhydroxides) under these conditions, lowering the concentration of free metal ions in the solution. For this reason, auxiliary complexing agents or ligands such as ammonia, tartrate, citrate, or triethanolamine are used in EDTA titrations to...

Qualitative Analysis

Qualitative Analysis

For solutions containing mixtures of different cations, the identity of each cation can be determined by qualitative analysis. This technique involves a series of selective precipitations with different chemical reagents, each reaction producing a characteristic precipitate for a specific group of cations. Metal ions within a group are further separated by varying the pH, heating the mixture to redissolve a precipitate, or adding other reagents to form complex ions.
For instance, group IV...

Complexation Equilibria: Factors Influencing Stability of Complexes

Complexation Equilibria: Factors Influencing Stability of Complexes

In complexation reactions, metal cations are the electron pair acceptors, and the ligands are the electron pair donors. The stability of the metal complexes depends primarily on the complexing ability of the central metal ion and the nature of the ligands. Generally, the complexing ability of the metal ion depends on the size and charge of the ion. As the metal ion size increases, the stability of the metal complexes decreases, provided that the valency of the metal ion and the ligands remain...

You might also read

Related Articles

Articles linked to this work by shared authors, journal, and citation graph.

Sort by

Same author

PPTMP: An Asymmetric Tetradentate Ligand for Trivalent Lanthanide/Actinide Separation in Nuclear Waste Management.

Inorganic chemistry·2026

Same author

Contrasting single-molecule magnet behaviour in dysprosium and terbium bis(stannolediide) complexes.

Nature chemistry·2026

Same author

Toward Understanding Prolate 4f Monomers: Numerical Predictions and Experimental Validation of Electronic Properties and Slow Relaxation in a Muffin-Shaped Er<sup>III</sup> Complex.

Inorganic chemistry·2026

Same author

Distinct Ligand- and Metal-Centered Phosphorescence in a Terbium Carbazolyl Complex.

Chemistry (Weinheim an der Bergstrasse, Germany)·2025

Same author

Ultrabroadband 1D and 2D NMR Spectroscopy.

Angewandte Chemie (International ed. in English)·2025

Same author

Pure Molecular Inorganic Rings: Mixed Group 14/15 Metallacycles.

Angewandte Chemie (International ed. in English)·2025

Search research articles

Related Experiment Video

Updated: Jul 5, 2026

Synthesis and Evaluation of a Ruthenium-based Mitochondrial Calcium Uptake Inhibitor

Synthesis and Evaluation of a Ruthenium-based Mitochondrial Calcium Uptake Inhibitor

Published on: October 26, 2017

Aminotroponiminate calcium and strontium complexes.

Simmi Datta¹, Michael T Gamer, Peter W Roesky

¹Institut für Chemie und Biochemie, Freie Universität Berlin, Fabeckstrabe 34-36, 14195, Berlin, Germany.

Dalton Transactions (Cambridge, England : 2003)

|May 15, 2008

Summary

New heteroleptic aminotroponiminate complexes of calcium and strontium were synthesized. Structural analysis revealed unique coordination modes, expanding the understanding of these metal-organic compounds.

More Related Videos

Monitoring ER/SR Calcium Release with the Targeted Ca2+ Sensor CatchER+

Monitoring ER/SR Calcium Release with the Targeted Ca²⁺ Sensor CatchER⁺

Published on: May 19, 2017

Loading a Calcium Dye into Frog Nerve Endings Through the Nerve Stump: Calcium Transient Registration in the Frog Neuromuscular Junction

Loading a Calcium Dye into Frog Nerve Endings Through the Nerve Stump: Calcium Transient Registration in the Frog Neuromuscular Junction

Published on: July 8, 2017

Related Experiment Videos

Last Updated: Jul 5, 2026

Synthesis and Evaluation of a Ruthenium-based Mitochondrial Calcium Uptake Inhibitor

Synthesis and Evaluation of a Ruthenium-based Mitochondrial Calcium Uptake Inhibitor

Published on: October 26, 2017

Monitoring ER/SR Calcium Release with the Targeted Ca2+ Sensor CatchER+

Monitoring ER/SR Calcium Release with the Targeted Ca²⁺ Sensor CatchER⁺

Published on: May 19, 2017

Loading a Calcium Dye into Frog Nerve Endings Through the Nerve Stump: Calcium Transient Registration in the Frog Neuromuscular Junction

Loading a Calcium Dye into Frog Nerve Endings Through the Nerve Stump: Calcium Transient Registration in the Frog Neuromuscular Junction

Published on: July 8, 2017

Area of Science:

Organometallic Chemistry
Coordination Chemistry

Background:

Aminotroponiminate ligands offer versatile coordination possibilities.
Calcium and strontium complexes are relevant in various chemical applications.

Purpose of the Study:

To synthesize and characterize novel heteroleptic aminotroponiminate complexes of calcium and strontium.
To investigate the structural diversity and coordination behavior of these complexes.

Main Methods:

Reaction of potassium aminotroponiminate salts with metal iodides.
Synthesis involving pre-formed metal amide precursors.
Single crystal X-ray diffraction for structural elucidation.

Main Results:

Preparation of monomeric calcium and dimeric strontium aminotroponiminate iodide complexes.
Synthesis of a mixed-ligand calcium complex via a non-metathesis route.
Formation of a diphosphanylamido calcium complex with eta2-coordination.

Conclusions:

Successfully synthesized a range of novel heteroleptic calcium and strontium complexes.
Demonstrated different synthetic strategies for accessing these compounds.
Provided detailed structural insights into ligand coordination in these metal complexes.