Two titanium centers (Asngbnd;Tisngbnd;HandBsngbnd;Tisngbnd;H) are formed in equal concentrations by reaction of hydrogen atoms with Ti4plus;in the agr;hyphen;quartz lattice at 120deg;K. Above 150deg;K,Bsngbnd;Tisngbnd;Htransforms intoAsngbnd;Tisngbnd;H. The spin Hamiltonians, including47,49Ti hyperfine and nuclear quadrupole terms, have been determined by 9.850hyphen;GHz EPR at 20deg;K, for both centers. These data, discussed from a crystalhyphen;field viewpoint and compared with results for analogous lithiumhyphen;compensated Ti3plus;centers, lead to a model for the centers involving a substitutional Ti3plus;ion with a nearby interstitial proton charge compensator located in either of two different sites.
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