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Updated: Jul 23, 2026
Multiscale Sampling of a Heterogeneous Water/Metal Catalyst Interface using Density Functional Theory and Force-Field Molecular Dynamics
Published on: April 12, 2019
(Tetrakis(2-pyridylmethyl)ethylenediamine)iron(II) perchlorate. Study of density functional methods
G Chen1, G Espinosa-Perez, A Zentella-Dehesa
1Chemistry Department, Beijing Normal University, Beijing 100875, China.
Abstract:
On the basis of the data obtained by X-ray diffraction, the properties of two independent crystallographic subsystems in the [Fe(tpen)](ClO4)2.2/3H2O complex are studied in detail with the density functional method B3LYP. The energies of singlet, triplet, and quintet states at different temperatures are obtained, the influences of geometry on energy changes are analyzed, the regularity of the spin-state interconversions is investigated, and the effect of the triplet and action of the anion on spin crossover are discussed. This investigation demonstrates that (1) the energy difference between the high-spin state and singlet state decreases as the Fe-N distance and geometric distortion increase, (2) the spin-equilibrium system is predominantly in low-spin form below room temperature and the proportion of high-spin state rapidly increases above room temperature, (3) one of the two cation sites has a greater presence of the high-spin content, (4) the triplet state may be responsible for the fast rate of spin-state interconversions, and (5) the B3LYP method proves to be very adequate to study the spin-state transition of this complex.
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