title: Modification of the magnetic properties of a heterometallic wheel by inclusion of a Jahn-Teller distorted Cu(II) ion.
abstract: An investigation into the physical consequences of including a Jahn-Teller distorted Cu(II) ion within an antiferromagnetically coupled ring, [R(2)NH(2)][Cr(7)CuF(8)((O(2)C(t)Bu)(16))] is reported. Inelastic neutron scattering (INS) and electron paramagnetic resonance (EPR) spectroscopic data are simulated using a microscopic spin Hamiltonian, and show that the two Cr-Cu exchange interactions must be inequivalent. One Cr-Cu exchange is found to be antiferromagnetic and the other ferromagnetic. The geometry of the Jahn-Teller elongation is deduced from these results, and shows that a Jahn-Teller elongation axis must lie in the plane of the Cr(7)Cu wheel; the elongation is not observed by X-ray crystallography, due to positional disorder of the Cu site within the wheel. An electronic structure calculation confirms the structural distortion of the Cu site.
authors: School of Chemistry, The University of Manchester, Oxford Road, Manchester, UK M13 9PL. michael.baker@postgrad.manchester.ac.uk
authors: Michael L
authors: ML
authors: Baker
authors: Stergios
authors: S
authors: Piligkos
authors: Alberto
authors: A
authors: Bianchi
authors: Stefano
authors: S
authors: Carretta
authors: David
authors: D
authors: Collison
authors: Joseph J W
authors: JJ
authors: McDouall
authors: Eric J L
authors: EJ
authors: McInnes
authors: Hannu
authors: H
authors: Mutka
authors: Grigore A
authors: GA
authors: Timco
authors: Floriana
authors: F
authors: Tuna
authors: Prabha
authors: P
authors: Vadivelu
authors: Høgni
authors: H
authors: Weihe
authors: Hans U
authors: HU
authors: Güdel
authors: Richard E P
authors: RE
authors: Winpenny