6533b834fe1ef96bd129d519
RESEARCH PRODUCT
Quadrupole splitting of Fe(II) spin crossover compounds study of temperature and pressure dependence and the implication for the interaction mechanism
Philipp GütlichH. KöppenHartmut SpieringL. WiehlE. Meissnersubject
Nuclear and High Energy PhysicsCondensed matter physicsSpin statesChemistryQuadrupole splittingCondensed Matter PhysicsAtomic and Molecular Physics and OpticsDeuteriumSpin crossoverLattice (order)Mössbauer spectroscopyMoleculePhysical and Theoretical ChemistryElectric field gradientdescription
The temperature and pressure dependence of the quadrupole splitting ΔE Q of the 3/2→1/2 nuclear Mossbauer transition of57Fe in the spin crossover compounds [Fe x Zn1−x (2-pic)3]Cl2⋆EtOH and the deuterated analog [Fe x Zn1−x (2-pic-ND2)3] Cl2⋆EtOD (2-pic=2-picolylamine) have been studied. The change of ΔE Q can be linearly related to the defomation of the lattice as observed by X-ray measurements. The dependence of ΔE Q on temperatureT, pressurep, and the fraction γ of molecules in the electronic high spin state in the pure iron (x=1) compounds is therefore interpreted as a result of the change of the lattice contribution to the electric field gradient (EFG) at the nucleus only. The intrinsic EFGs of the molecules remain unchanged under the cooperative interaction of the spin crossover complex molecules. This fact is consistent with a simple elastic interaction between the complexes rather than a Jahn-Teller-type of interaction also discussed in the literature.
| year | journal | country | edition | language |
|---|---|---|---|---|
| 1989-06-01 | Hyperfine Interactions |