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Thermochemical Studies of Ni(II) and Zn(II) Ternary Complexes Using Ion Mobility-Mass Spectrometry
Published on: June 8, 2022
A new structural technique for examining ion-neutral association in aqueous solution.
Philip E Mason1, George W Neilson, David L Price
1Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, Flemingovo nám. 2, 16610 Prague 6, Czech Republic. phil.mason@marge.uochb.cas.cz
Faraday Discussions
|June 26, 2013
Summary
The intramolecular coordination number concentration invariance (ICNCI) method, using neutron diffraction with isotopic substitution (NDIS), effectively separates molecular interactions in solutions. Molecular dynamics simulations validate this for some solutes, but reveal limitations for others, impacting Hofmeister series studies.
Area of Science:
- Physical Chemistry
- Solution Chemistry
- Biophysical Chemistry
Background:
- Understanding solute-solvent interactions is crucial for chemical and biological processes.
- Distinguishing intra- and intermolecular forces in solutions remains a challenge.
- Molecular dynamics (MD) simulations offer atomic-level insights but require validation.
Purpose of the Study:
- To apply the intramolecular coordination number concentration invariance (ICNCI) method to neutron diffraction with isotopic substitution (NDIS) data.
- To validate MD simulations in replicating ICNCI functions for aqueous solutions.
- To assess the accuracy of MD in modeling solute-solute interactions, particularly in the context of the Hofmeister series.
Main Methods:
- Utilized neutron diffraction with isotopic substitution (NDIS) measurements.
- Employed the intramolecular coordination number concentration invariance (ICNCI) method to analyze diffraction data.
- Performed molecular dynamics (MD) simulations for aqueous solutions of xylose, pyridine, and pyridine with guanidinium salts.
Main Results:
- The ICNCI function accurately reflects intermolecular association in aqueous solutions.
- MD simulations successfully replicated ICNCI functions for xylose and pyridine.
- MD simulations failed to accurately replicate the ICNCI function for pyridine with guanidinium sulfate, indicating overestimated interactions.
Conclusions:
- The ICNCI method is a valuable tool for dissecting intra- and intermolecular contributions in solutions.
- MD simulations are reliable for certain solute-solvent systems but require careful validation for complex interactions.
- Discrepancies in MD simulations highlight the need for improved force fields to accurately model the Hofmeister series.
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