Crystal field effect on EPR and optical absorption properties of natural green zoisite

Henry Javier-Ccallata; Shigueo Watanabe

doi:10.1016/j.saa.2012.11.099

Crystal field effect on EPR and optical absorption properties of natural green zoisite

Henry Javier-Ccallata, Shigueo Watanabe

Research output: Contribution to journal › Article › peer-review

Abstract

In this study the electron paramagnetic resonance (EPR) and optical absorption (OA) of natural crystal of zoisite were investigated after γ (⁶⁰Co) irradiation and high temperature annealing. EPR measurements show that the zoisite from Tefilo Otoni MG Brazil contain Cr³⁺, Fe³⁺ and Mn²⁺ ions and occupy distorted Al³⁺ octahedral and tetrahedral sites which are subjected to the action of a strong crystal field in axial direction. Absorption bands which in principle give rise to sets of EPR lines between 500 and 2500 G were found using the deconvolution method. The application of high doses of gamma ray and high temperature annealing has shown no significant effects on EPR and OA spectra. Spin-allowed, spin-forbidden and crystal field parameters were calculated for 3d³ configuration and interpreted using the spin Hamiltonian formalism containing axial and rhombic terms in low symmetries.

Original language	English
Pages (from-to)	505-511
Number of pages	7
Journal	Spectrochimica Acta - Part A: Molecular and Biomolecular Spectroscopy
Volume	104
DOIs	https://doi.org/10.1016/j.saa.2012.11.099
State	Published - Mar 2013
Externally published	Yes

Bibliographical note

Funding Information:
We would like to thank Ms. E. Somesari and Mr. C. Gaia for kindly carrying out irradiation of the samples. This work was supported by CAPES and FAPESP.

Keywords

Annealing
Crystal field
EPR
Optical absorption
Zoisite

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10.1016/j.saa.2012.11.099

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title = "Crystal field effect on EPR and optical absorption properties of natural green zoisite",

abstract = "In this study the electron paramagnetic resonance (EPR) and optical absorption (OA) of natural crystal of zoisite were investigated after γ (60Co) irradiation and high temperature annealing. EPR measurements show that the zoisite from Tefilo Otoni MG Brazil contain Cr3+, Fe3+ and Mn2+ ions and occupy distorted Al3+ octahedral and tetrahedral sites which are subjected to the action of a strong crystal field in axial direction. Absorption bands which in principle give rise to sets of EPR lines between 500 and 2500 G were found using the deconvolution method. The application of high doses of gamma ray and high temperature annealing has shown no significant effects on EPR and OA spectra. Spin-allowed, spin-forbidden and crystal field parameters were calculated for 3d3 configuration and interpreted using the spin Hamiltonian formalism containing axial and rhombic terms in low symmetries.",

keywords = "Annealing, Crystal field, EPR, Optical absorption, Zoisite",

author = "Henry Javier-Ccallata and Shigueo Watanabe",

note = "Funding Information: We would like to thank Ms. E. Somesari and Mr. C. Gaia for kindly carrying out irradiation of the samples. This work was supported by CAPES and FAPESP.",

year = "2013",

month = mar,

doi = "10.1016/j.saa.2012.11.099",

language = "Ingl{\'e}s",

volume = "104",

pages = "505--511",

journal = "Spectrochimica Acta - Part A: Molecular and Biomolecular Spectroscopy",

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TY - JOUR

T1 - Crystal field effect on EPR and optical absorption properties of natural green zoisite

AU - Javier-Ccallata, Henry

AU - Watanabe, Shigueo

N1 - Funding Information: We would like to thank Ms. E. Somesari and Mr. C. Gaia for kindly carrying out irradiation of the samples. This work was supported by CAPES and FAPESP.

PY - 2013/3

Y1 - 2013/3

N2 - In this study the electron paramagnetic resonance (EPR) and optical absorption (OA) of natural crystal of zoisite were investigated after γ (60Co) irradiation and high temperature annealing. EPR measurements show that the zoisite from Tefilo Otoni MG Brazil contain Cr3+, Fe3+ and Mn2+ ions and occupy distorted Al3+ octahedral and tetrahedral sites which are subjected to the action of a strong crystal field in axial direction. Absorption bands which in principle give rise to sets of EPR lines between 500 and 2500 G were found using the deconvolution method. The application of high doses of gamma ray and high temperature annealing has shown no significant effects on EPR and OA spectra. Spin-allowed, spin-forbidden and crystal field parameters were calculated for 3d3 configuration and interpreted using the spin Hamiltonian formalism containing axial and rhombic terms in low symmetries.

AB - In this study the electron paramagnetic resonance (EPR) and optical absorption (OA) of natural crystal of zoisite were investigated after γ (60Co) irradiation and high temperature annealing. EPR measurements show that the zoisite from Tefilo Otoni MG Brazil contain Cr3+, Fe3+ and Mn2+ ions and occupy distorted Al3+ octahedral and tetrahedral sites which are subjected to the action of a strong crystal field in axial direction. Absorption bands which in principle give rise to sets of EPR lines between 500 and 2500 G were found using the deconvolution method. The application of high doses of gamma ray and high temperature annealing has shown no significant effects on EPR and OA spectra. Spin-allowed, spin-forbidden and crystal field parameters were calculated for 3d3 configuration and interpreted using the spin Hamiltonian formalism containing axial and rhombic terms in low symmetries.

KW - Annealing

KW - Crystal field

KW - EPR

KW - Optical absorption

KW - Zoisite

UR - http://www.scopus.com/inward/record.url?scp=84871715642&partnerID=8YFLogxK

U2 - 10.1016/j.saa.2012.11.099

DO - 10.1016/j.saa.2012.11.099

M3 - Artículo

C2 - 23291113

AN - SCOPUS:84871715642

VL - 104

SP - 505

EP - 511

JO - Spectrochimica Acta - Part A: Molecular and Biomolecular Spectroscopy

JF - Spectrochimica Acta - Part A: Molecular and Biomolecular Spectroscopy

SN - 1386-1425

ER -

Crystal field effect on EPR and optical absorption properties of natural green zoisite

Abstract

Bibliographical note

Keywords

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