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Assessment of the Density Functional Tight Binding Method for Protic Ionic Liquids.

ABSTRACT: Density functional tight binding (DFTB), which is ?100-1000 times faster than full density functional theory (DFT), has been used to simulate the structure and properties of protic ionic liquid (IL) ions, clusters of ions and the bulk liquid. Proton affinities for a wide range of IL cations and anions determined using DFTB generally reproduce G3B3 values to within 5-10 kcal/mol. The structures and thermodynamic stabilities of n-alkyl ammonium nitrate clusters (up to 450 quantum chemical atoms) predicted with DFTB are in excellent agreement with those determined using DFT. The IL bulk structure simulated using DFTB with periodic boundary conditions is in excellent agreement with published neutron diffraction data.

SUBMITTER: Addicoat MA

PROVIDER: S-EPMC4196743 | biostudies-literature | 2014 Oct

REPOSITORIES: biostudies-literature

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Assessment of the Density Functional Tight Binding Method for Protic Ionic Liquids.

Addicoat Matthew A MA Stefanovic Ryan R Webber Grant B GB Atkin Rob R Page Alister J AJ

Journal of chemical theory and computation 20140827 10

Density functional tight binding (DFTB), which is ∼100-1000 times faster than full density functional theory (DFT), has been used to simulate the structure and properties of protic ionic liquid (IL) ions, clusters of ions and the bulk liquid. Proton affinities for a wide range of IL cations and anions determined using DFTB generally reproduce G3B3 values to within 5-10 kcal/mol. The structures and thermodynamic stabilities of <i>n</i>-alkyl ammonium nitrate clusters (up to 450 quantum chemical a ...[more]

PMID: 25328497

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