Record Details

Magnetic Relaxation in Single-Electron Single-Ion Cerium(III) Magnets: Insights from Ab Initio Calculations

DSpace at IIT Bombay

View Archive Info
 
 
Field Value
 
Title Magnetic Relaxation in Single-Electron Single-Ion Cerium(III) Magnets: Insights from Ab Initio Calculations
 
Creator SINGH, SK
GUPTA, T
UNGUR, L
RAJARAMAN, G
 
Subject MOLECULE-MAGNET
GROUND-STATE
URANIUM(III) COMPLEX
LANTHANIDE COMPLEXES
EXCITED-STATE
SMM BEHAVIOR
DOMAIN-WALL
ANISOTROPY
BLOCKING
DY
cerium
density functional calculations
ligand effects
magnetic properties
 
Description Detailed ab initio calculations were performed on two structurally different cerium(III) single-molecule magnets (SMMs) to probe the origin of magnetic anisotropy and to understand the mechanism of magnetic relaxations. The complexes [Ce-III{Zn-II(L)}(2)(MeOH)]BPh4 (1) and [Li(dme)(3)][Ce-III(cot)(2)] (1; L=N,N,O,O-tetradentate Schiff base ligand; 2; DME=dimethoxyethane, COT=1,4-bis(trimethylsilyl)cyclooctatetraenyldianion), which are reported to be zero-field and field-induced SMMs with effective barrier heights of 21.2 and 30K respectively, were chosen as examples. CASSCF+RASSI/SINGLE_ANISO calculations unequivocally suggest that m(J)|+/- 5/2 and |+/- 1/2 are the ground states for complexes 1 and 2, respectively. The origin of these differences is rooted back to the nature of the ligand field and the symmetry around the cerium(III) ions. Ab initio magnetisation blockade barriers constructed for complexes 1 and 2 expose a contrasting energy-level pattern with significant quantum tunnelling of magnetisation between the ground state Kramers doublet in complex 2. Calculations performed on several model complexes stress the need for a suitable ligand environment and high symmetry around the cerium(III) ions to obtain a large effective barrier.
 
Publisher WILEY-V C H VERLAG GMBH
 
Date 2016-01-14T10:30:38Z
2016-01-14T10:30:38Z
2015
 
Type Article
 
Identifier CHEMISTRY-A EUROPEAN JOURNAL, 21(39)13812-13819
0947-6539
1521-3765
http://dx.doi.org/10.1002/chem.201501330
http://dspace.library.iitb.ac.in/jspui/handle/100/17364
 
Language en