Related Experiment Video
Updated: Jul 1, 2026

Structure and Coordination Determination of Peptide-metal Complexes Using 1D and 2D 1H NMR
Published on: December 16, 2013
Europium Coordination Structure in Peptide Complexes Resolved with Simulation and X-ray Absorption Spectroscopy
Sina Chiniforoush1, Shelly D Kelly2, Oksana Fizer3
1Department of Chemical and Materials Engineering, University of Nevada, Reno, Reno, Nevada 89557, United States.
None:
The study of the coordination structure in lanthanide-ligand complexes is important to gain insight into the selectivity of ligands for specific lanthanide ions. We recently designed lanthanide binding cyclic peptides (LBCPs), which display selectivity toward the middle lanthanides. In this study, we report micromolar affinity in a Eu-LBCP complex and resolve the structure of the europium complexes with two LBCPs by comparing experimental extended X-ray absorption fine structure (EXAFS) spectra to ensemble-average spectra derived from molecular dynamics (MD) simulation, as well as to spectra from a fitting model. Our results show agreement between the computationally derived and experimentally measured EXAFS spectra, which supports the predicted Eu coordination structure in LBCP complexes, as well as the utility of combining molecular simulation and EXAFS to study the structure of lanthanide-ligand complexes in solution.
More Related Videos
11:04Ion Mobility-Mass Spectrometry Techniques for Determining the Structure and Mechanisms of Metal Ion Recognition and Redox Activity of Metal Binding Oligopeptides
Published on: September 7, 2019
08:54Vibrational Spectra of a N719-Chromophore/Titania Interface from Empirical-Potential Molecular-Dynamics Simulation, Solvated by a Room Temperature Ionic Liquid
Published on: January 25, 2020
Related Concept Videos
Colors and Magnetism
When atoms or molecules absorb light at the proper frequency, their electrons are excited to higher-energy orbitals. For many main group atoms and molecules, the absorbed photons are in the ultraviolet range of the electromagnetic spectrum, which cannot be detected by the human eye. For coordination compounds, the energy difference between the d orbitals often allows photons in the visible range to be absorbed and emitted, which is seen as colors by the human eye.
Valence Bond Theory
Stereoisomerism
Isomers are different chemical species that have the same chemical formula.
Transition metal complexes often exist as geometric isomers, in which the same atoms are connected through the same types of bonds but with differences in their orientation in space. Coordination complexes with two different ligands in the cis and trans positions from a ligand of interest form isomers. For example, the octahedral [Co(NH3)4Cl2]+ ion has two isomers (Figure 1) In the cis...