6533b86efe1ef96bd12cb1ee
RESEARCH PRODUCT
Dynamics of BF 4 - anion reorientation in the spin-crossover compound [Fe(1-n-propyl-1H-tetrazole) 6 ](BF 4 ) 2 and in its Zn II analogue
P. GütlichT. MarekKálmán TompaMónika BokorA. Vértessubject
Lattice dynamicschemistry.chemical_compoundParamagnetismCrystallographyTetrafluoroborateNuclear magnetic resonancechemistrySpin crossoverSpin–lattice relaxationCrystal structure1H-tetrazoleAtomic and Molecular Physics and OpticsIondescription
19 F and 11 B spin-lattice relaxation times were measured in [ Zn ( ptz ) 6 ] ( BF 4 ) 2 and in the spin-crossover compound [ Fe ( ptz ) 6 ] ( BF 4 ) 2 . For both compounds BF 4 - anion reorientation is active above 50 K. For [ Zn ( ptz ) 6 ] ( BF 4 ) 2 , the anion-reorientation dynamics is different in the temperature regions of 50-90 K, 90-120 K, and above 150 K; between 120 and 150 K it changes rapidly reflecting a structural change. In [ Fe ( ptz ) 6 ] ( BF 4 ) 2 the mechanism for the paramagnetic relaxation involving the 19 F nuclei is found to be of the diffusion-limited type according to the theory of Lowe and Tse. The present results prove that the spin-crossover takes place in a dynamic surrounding and not in a static crystal lattice.
| year | journal | country | edition | language |
|---|---|---|---|---|
| 1999-12-31 | The European Physical Journal D - Atomic, Molecular and Optical Physics |