0000000000341546
AUTHOR
Christian Von Malotki
showing 2 related works from this author
Spin transition in three-dimensional bridged coordination polymers of iron(II)–urea-triazoles
2008
Abstract Three-dimensional spin-crossover (SCO) networks of [Fe 2 ( n -Rdubtrz) 3 ](X) 4 · n H 2 O ( n -R = (CH 2 ) y , y = 4, 6, 8, 12; du = diurea; btrz = bis-triazole; X = BF 4 - , ClO 4 - , triflate, tosylate) coordination polymers are prepared by reaction of bridging aliphatic bis-urea triazoles ( n -Rdubtrz) with the iron-salts (FeX 2 ). Investigations of the properties are supported by studies of one-dimensional compounds of [Fe(Rtrzu) 3 ](X) 2 (R = n -propyl, t -butyl; trzu = urea triazole). Characterization of the complexes is carried out with IR-spectroscopy, elemental analysis, TGA and atomic absorption spectroscopy. SCO-behaviour of all complexes is inspected by magnetic sus…
Vibrational properties of 1D- and 3D polynuclear spin crossover Fe(II) urea-triazoles polymer chains and quantification of intrachain cooperativity
2020
Abstract The vibrational dynamics of the iron centres in 1D and 3D spin crossover Fe(II) 4-alkyl-urea triazole chains have been investigated by synchrotron based nuclear inelastic scattering. For the 1D system, the partial density of phonon states has been modelled with density functional theory methods. Furthermore, spin dependent iron ligand distances and vibrational modes were obtained. The previously introduced intramolecular cooperativity parameter H coop (Rackwitz et al, Phys. Chem. Chem. Phys. 2013, 15, 15450) has been determined to −31 kJ mol−1 for [Fe(n-Prtrzu)3(tosylate)2] and to +27 kJ mol−1 for [Fe(n-Prtrzu)3(BF4)2]. The change of sign in H coop is in line with the incomplete an…