Interactions between Keggin Anions in Water: The Higher Their Charge, the Higher Their Condensation? A Simulation Study

Abstract

We report molecular dynamics (MD) 5-), the aim of which was to investigate whether the anions increasingly repulse each other in water when their charge increases from -3 to -5. The MD and PMF (potential of mean force) results indicate that this is not the case. All three anions are found to display short XW n-

Beyond Charge Balance: Counter‐Cations in Polyoxometalate Chemistry

“…Information on dynamic processes of POM-cation interactions can be accessed by classical and ab initio molecular dynamics (MD) simulations. [55][56][57][58] For example, MD was used in conjunction with the above-mentioned microscopy study, and both independently showed formation of POM-pairs linked by Na + , also consistent with the solid-state structure. [51] In summary, the combination of experiment and theory can potentially provide powerful and accurate information about POM-cation interactions in solution, guiding future developments of new POM architectures and superstructures.…”

“…Thereby, experimentally accessible data such as vibrational or electronic absorption properties can be calculated from first principles, and characteristic features of the POM–cation interactions can be identified. Information on dynamic processes of POM–cation interactions can be accessed by classical and ab initio molecular dynamics (MD) simulations . For example, MD was used in conjunction with the above‐mentioned microscopy study, and both independently showed formation of POM‐pairs linked by Na + , also consistent with the solid‐state structure .…”

Maximizing Headgroup Repulsion: Hybrid Surfactants with Ultrahighly Charged Inorganic Heads and Their Unusual Self-Assembly

“…Is has been shown among others by Liu 21 and Weinstock 22 that self-assembly of POM clusters is affected by the counterions. Molecular dynamic simulations of Keggin clusters in acid aqueous environment performed by Chaumont and Wipff 23 also show that SiW 12 O 40 4– exhibits a larger tendency of aggregation compared to PW 12 O 40 3– , despite its higher charge. Furthermore, they found that the distance between the aggregated clusters changes only marginally (0.1 Å).…”

Jenseits von Ladungsausgleich: Gegenkationen in der Polyoxometallat‐Chemie

“…Dadurch können experimentell beobachtbare Daten wie Schwingungs‐ und elektronische Absorptionsspektren basierend auf Ab‐initio‐Methoden berechnet und charakteristische Eigenschaften der POM‐Kation‐Wechselwirkungen identifiziert werden. Informationen über dynamische Prozesse der POM‐Kation‐Wechselwirkungen können zudem durch klassische und Ab‐initio‐Moleküldynamik(MD)‐Simulationen zugänglich gemacht werden . So wurde z.…”

“…Informationen über dynamische Prozesse der POM-Kation-Wechselwirkungen kçnnen zudem durch klassische und Ab-initio-Moleküldynamik(MD)-Simulationen zugänglich gemacht werden. [55][56][57][58] So wurde z. B. MD zusammen mit der oben beschriebenen Mikroskopiestudie genutzt, um unabhängig voneinander die Bildung von Na + -verknüpften POM-Paaren nachzuweisen, was auch konsistent mit der beobachteten Festkçrperstruktur war.…”