@misc{10481/57618,
year = {2018},
month = {11},
url = {http://hdl.handle.net/10481/57618},
abstract = {Chiral bipyrimidine-bridged dinuclear LnIII complexes of general formula
[(μ-bipym){((+)-tfacam)3Ln}2] and [(μ-bipym){((-)-tfacam)3Ln}2], have been prepared
from the assembly of Ln(AcO)3·nH2O (LnIII = Dy, Gd), (+)/(−)-3-(trifluoroacetyl)camphor
enantiopure ligands ((+)/(-)-Htfacam) and bipyrimidine (bipym). The structure and
chirality of these complexes have been supported by single-crystal X-Ray diffraction
and circular dichroism. The study of the magnetic properties of the GdIII complexes
revealed a very weak antiferromagnetic interaction between the GdIII ions through the
bipyrimidine bridging ligand. Ab initio CASSCF calculations indicated that the ground
Kramers doublet (KD) of both DyIII centers is almost purely axial with the anisotropy axis
located close to the two tfacam−ligands at opposite sides of each DyIIIatom, which
create an axial crystal field. In keeping with this, ac dynamic measurements indicated
slow relaxation of the magnetization at zero field with Ueff = 55.1 K, a pre-exponential
factor of τo = 2.17·10−6 s and τQTM = 8 μs. When an optimal dc field of 0.1 T is
applied, QTM is quenched and Ueff increases to 75.9 K with τo = 6.16 × 10−7 s. The
DyN2O8 coordination spheres and SMM properties of [(μ-bipym){((+)-tfacam)3Ln}2]
and their achiral [(Dy(b-diketonate)3)2(μ-bpym)]analogous have been compared and a
magneto-structural correlation has been established, which has been supported by
theoretical calculations.},
organization = {ID-O, JH, and EC are grateful to Ministerio de Economía y
Competitividad (MINECO) for Project CTQ2014-56312-P, the
Junta de Andalucía (FQM-195 and the Project of excellence
P11-FQM-7756) and the University of Granada. A part of this
work has been made at HFLSM, IMR, Tohoku University. IDO
also acknowledges support by COLABS. GR would like to
thank SERB (EMR/2014/000247) for financial support. SDthanks
UGC for Senior Research Fellowship. AC thanks the Marie
Curie COFUND Action from the European Commission for
co-financing his postdoctoral fellowship.},
publisher = {Frontiers Media},
keywords = {Bipyrimidine-bridged},
keywords = {Ab initio calculations},
keywords = {Magnetic properties},
keywords = {Diketonates},
title = {A Chiral Bipyrimidine-Bridged Dy2 SMM: A Comparative Experimental and Theoretical Study of the Correlation Between the Distortion of the DyO6N2 Coordination Sphere and the Anisotropy Barrier},
doi = {10.3389/fchem.2018.00537},
author = {Diaz Ortega, Ismael and Herrera Martínez, Juan Manuel and Reyes Carmona, Álvaro and Galán Mascarós, Jose Ramón and Dey, Sourav and Nojiri, Hiroyuki and Rajaraman, Gopalan and Colacio Rodríguez, Enrique},
}