New E′ centers in neutron-irradiated α-quartz
1 V.S. Sobolev Institute of Geology and Mineralogy SB RAS - 630090 Novosibirsk, Russia
2 Department of Geological Sciences, University of Saskatchewan - Saskatoon, Saskatchewan, S7N 5E2 Canada
Received: 7 March 2016
Accepted: 1 April 2016
Several E′-type defects have been revealed in neutron-irradiated natural and synthetic α-quartz by using electron paramagnetic resonance (EPR) spectroscopy. For the known center the primary spin Hamiltonian parameter matrices g and A(29Si) (hyperfine interaction with 29Si) have been refined and provide compelling evidence for spin trapping on the long-bond Si atom. The EPR spectra of the new center demonstrate that the super-hyperfine structure arises from the interaction with 27Al, the first-ever example of Al-associated E′ centers in crystalline quartz. The matrices g and A(29Si) of and another new center support the forward-oriented configuration proposed for the center in amorphous silica.
PACS: 42.70.Ce – Glasses, quartz / 61.72.jd – Vacancies / 61.72.J- – Point defects and defect clusters
© EPLA, 2016