Premium
Effect of lattice defects in divalent lattices by incorporating trivalent ions in biominerals: An EPR study of Cr(III) in zinc(II) potassium phosphate hexahydrate
Author(s) -
Anandalakshmi H.,
Venkatesan R.,
Sambasiva Rao P.
Publication year - 2004
Publication title -
crystal research and technology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.377
H-Index - 64
eISSN - 1521-4079
pISSN - 0232-1300
DOI - 10.1002/crat.200310152
Subject(s) - electron paramagnetic resonance , chemistry , divalent , zinc , crystallography , ion , potassium phosphate , potassium , crystal structure , nuclear magnetic resonance , physics , organic chemistry , chromatography
In order to understand the effect of charge compensating vacancies on the number, orientation and magnitude of D‐tensors, single crystal EPR measurements have been carried out with Cr(III) in zinc(II) potassium phosphate hexahydrate at room temperature. During crystal rotations, a maximum of 6/7 resonance lines or a minimum of 2 is noticed. Crystal rotations done in the three orthogonal planes have yielded spin Hamiltonian parameters for one site with: g xx =1.969, g yy = 1.995, g zz = 2.107; D xx = 66.2 mT; D yy = 91.7 mT, and D zz =‐157.9 mT. The powder EPR spectrum indicates a very broad line at g = 8, without any extra resonances from 0 to 650 mT both at room temperature and 77 K. The reason may be that due to large zero field splitting, the resonance at g = 2 is shifted to g = 8 position and the other resonances are below 0 or above 650 mT. (© 2004 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)