Skip to main content

A homologous series of [Fe(H2Bpz2)2(L)] spin-crossover complexes with annelated bipyridyl co-ligands

Kulmaczewski, R., Shepherd, H.J., Cespedes, O., Halcrow, M.A. (2014) A homologous series of [Fe(H2Bpz2)2(L)] spin-crossover complexes with annelated bipyridyl co-ligands. Inorganic Chemistry, 53 (18). pp. 9809-9817. ISSN 00201669 (ISSN). (doi:10.1021/ic501402q) (The full text of this publication is not currently available from this repository. You may be able to access a copy if URLs are provided)

The full text of this publication is not currently available from this repository. You may be able to access a copy if URLs are provided. (Contact us about this Publication)
Official URL
http://www.scopus.com/inward/record.url?eid=2-s2.0...

Abstract

Four new iron(II) complexes [Fe- (H2Bpz2)2(L)] were prepared (pz = pyrazolyl), where L is dipyrido[3,2-f:2',3'-h]quinoxaline (dpq), dipyrido[3,2-a:2'3'- c]phenazine (dppz), dipyrido[3,2-a:2'3'-c]benzo[i]-phenazine (dppn), and dipyrido[3,2-a:2',3'-c](6,7,8,9-tetrahydro)- phenazine (dppc). Crystal structures of [Fe(H2Bpz2)2(dpq)], [Fe(H2Bpz2)2(dppz)], and [Fe(H2Bpz2)2(dppn)] all reveal stacks of complex molecules formed through Ï?-Ï? stacking between interdigitated bipyridyl chelate ligands, often with additional intercalated toluene or uncoordinated bipyridyl ligand (dpq). Molecules of [Fe(H2Bpz2)2(dppc)] form a different stacking motif in the crystal, with weaker contacts between individual molecules. Many of the structures also contain channels of disordered solvent, running between the molecular stacks. Despite their different stacking motifs, all these compounds exhibit very gradual thermal spin-crossover (SCO) on cooling, which occur over different temperature ranges but are otherwise quite similar in form. Weak thermal hysteresis in one of these spin equilibria can be attributed to the effects of a change in bipyridyl ligand conformation in the molecular stacks around 150 K, which was observed crystallographically. These results demonstrate that strong mechanical coupling between molecules in a crystal is not sufficient to engineer cooperative SCO switching, if other regions of the lattice are less densely packed.

Item Type: Article
DOI/Identification number: 10.1021/ic501402q
Additional information: Unmapped bibliographic data: LA - English [Field not mapped to EPrints] J2 - Inorg. Chem. [Field not mapped to EPrints] AD - School of Chemistry, University of Leeds, Woodhouse Lane, Leeds, United Kingdom [Field not mapped to EPrints] AD - Department of Chemistry, University of Bath, Claverton Down, Bath, United Kingdom [Field not mapped to EPrints] AD - School of Physics and Astronomy, University of Leeds, E. C. Stoner Building, Leeds, United Kingdom [Field not mapped to EPrints] DB - Scopus [Field not mapped to EPrints]
Subjects: Q Science > QD Chemistry > QD473 Physical properties in relation to structure
Divisions: Faculties > Sciences > School of Physical Sciences > Functional Materials Group
Depositing User: Giles Tarver
Date Deposited: 21 Oct 2015 16:03 UTC
Last Modified: 23 Jan 2020 04:10 UTC
Resource URI: https://kar.kent.ac.uk/id/eprint/50812 (The current URI for this page, for reference purposes)
Shepherd, H.J.: https://orcid.org/0000-0003-0832-4475
  • Depositors only (login required):