First principles calculation of a large variation in dielectric tensor through the spin crossover in the CsFe[Cr(CN){sub 6}] Prussian blue analogue
- Inorganic Computational Chemistry Group, Department of Chemistry, University of Warwick, Coventry CV4 7AL (United Kingdom)
The dielectric response of spin-crossover (SCO) materials is a key property facilitating their use in next-generation information processing technologies. Solid state hybrid density functional theory calculations show that the temperature-induced and strongly hysteretic SCO transition in the Cs{sup +}Fe{sup 2+}[Cr{sup 3+}(CN{sup −}){sub 6}] Prussian blue analogue (PBA) is associated with a large change (Δ) in both the static, Δε{sup 0}(HS − LS), and high frequency, Δε{sup ∞}(HS − LS) dielectric constants. The SCO-induced variation in CsFe[Cr(CN){sub 6}] is significantly greater than the experimental Δε values observed previously in other SCO materials. The phonon contribution, Δε{sup phon}(HS − LS), determined within a lattice dynamics approach, dominates over the clamped nuclei term, Δε{sup ∞}(HS − LS), and is in turn dominated by the low-frequency translational motions of Cs{sup +} cations within the cubic voids of the Fe[Cr(CN){sub 6}]{sup −} framework. The Cs{sup +} translational modes couple strongly to the large unit cell volume change occurring through the SCO transition. PBAs and associated metal-organic frameworks emerge as a potentially fruitful class of materials in which to search for SCO transitions associated with large changes in dielectric response and other macroscopic properties.
- OSTI ID:
- 22253284
- Journal Information:
- Journal of Chemical Physics, Vol. 140, Issue 14; Other Information: (c) 2014 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA); ISSN 0021-9606
- Country of Publication:
- United States
- Language:
- English
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