Spin crossover modulation in a coordination polymer with the redox-active bis-pyridyltetrathiafulvalene (py₂TTF) ligand

Abstract

A 1-D chain CP with both SCO and redox activity has been successfully prepared by the combination of a bis-pyridyl functionalised TTF core and a Schiff base-like N2O2 ligand.

Spin States of 1D Iron(II) Coordination Polymers with Redox Active TTF(py)2 as Bridging Ligand

“…(see Figure S3, Supporting Information). Strikingly, the previously published crystals of 1c conserve the HS state down to 100 K. [ 24 ]…”

“…Reproduction of the compounds in the respective medium always provided the same elemental analysis results. The synthesis, single‐crystal X‐ray structure and solid‐state redox properties of 1c have been recently communicated, [ 24 ] but will be covered in more detail with regard to the properties in solution herein.…”

“…In the rich literature on solid‐state structures of TTF derivatives, stacking of adjacent TTF units is a recurrent motif which often dominates among the non‐covalent interactions and serves to define the packing. [ 14,31,32 ] For instance, the single crystals of the recently reported iron(II) coordination polymer 1c , [ 24 ] feature extensive stacking of adjacent TTF units. By contrast, TTF units do not stack among themselves in C2a .…”

“…This approach complements a recent theoretical study wherein we approximated the electronic properties of polymer 1 as the mononuclear complex [FeL1(pyTTF) 2 ], carrying two axially coordinated TTF units. [ 24 ] The metrics were optimized with the BP86 functional and large TZVP basis sets. This setting has been found suitable to match the metrics of iron(II) complexes in a number of previous cases.…”

“…[ 3,18,19,20 ] As a large number of interesting iron(II) coordination polymers with descendants of bidentate pyridine‐containing ligands is known, [ 3,18,21 ] the ligand 2,6(7)‐bis(4‐pyridyl)‐1,4,5,8‐tetrathiafulvalene (TTF(py) 2 ) reported 2007 by Han et al, is an interesting aspirant for the synthesis of coordination polymers combining SCO behavior and redox active properties. [ 22,23 ] The combination of these two systems in a 1D coordination polymer, has recently been communicated to be successful [ 24 ] and will be further deepened in the course of this work. Herein we investigate the impact of solvents used during the synthesis of two different coordination polymers on their magnetic properties.…”