Anion-π recognition between [M(CN)6]3- complexes and HAT(CN)6: structural matching and electronic charge density
Jedrzej Kobylarczyk1, Dawid Pinkowicz1, Monika Srebro-Hooper1
1Faculty of Chemistry, Jagiellonian University in Kraków, Ingardena 3, 30-060 Kraków, Poland. robert.podgajny@uj.edu.pl.
Dalton Transactions (Cambridge, England : 2003)
|March 3, 2017
Summary
Novel molecular networks form through anion-π interactions between metal hexacyanidometalates and HAT(CN)6. These self-assembled structures exhibit charge-transfer and polarization, persisting in solution.
Area of Science:
- Supramolecular Chemistry
- Materials Science
- Coordination Chemistry
Background:
- Metal hexacyanidometalates and multisite anion receptors like HAT(CN)6 are key components in supramolecular assembly.
- Understanding intermolecular interactions is crucial for designing novel molecular networks.
Purpose of the Study:
- To investigate the self-assembly of hexacyanidometalates (M = FeIII, CoIII) with HAT(CN)6.
- To characterize the resulting molecular networks and the nature of their interactions.
- To explore the charge-transfer and polarization characteristics of these supramolecular synthons.
Main Methods:
- Synthesis and characterization of novel molecular networks (PPh4)3[M(CN)6][HAT(CN)6] and (AsPh4)3[M(CN)6][HAT(CN)6]·2MeCN·H2O.
- Physicochemical characterization including IR spectroscopy, UV-Vis spectroscopy, and cyclic voltammetry.
- Dispersion-corrected DFT studies for electronic structure and interaction energy calculations.
Main Results:
- Formation of stacked columns {[M(CN)6]3-;[HAT(CN)6]}∞ stabilized by collective triple anion-π interactions.
- Identification of charge-transfer and polarization as dominant interaction characters, with electron density flow from [M(CN)6]3- to HAT(CN)6.
- UV-Vis spectroscopy confirmed persistent intermolecular interactions in solution, suggesting a 1:1 anion-π {[M(CN)6]3-;[HAT(CN)6]} chromophore.
Conclusions:
- The study successfully demonstrates the self-assembly of novel molecular networks driven by anion-π interactions.
- These interactions are characterized by significant charge-transfer and polarization effects.
- The findings provide insights into the design principles for supramolecular materials with tunable electronic properties.
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