Negative ENDOR study of the radiation damage in triglycine sulphate

An ENDOR study of irradiated TGS crystals was conducted, and it was found that in the ferroelectric phase the splitting of a proton signal decreased with increasing doses of irradiation. This decrease was interpreted in terms of a reduction in a parameter $\text{σ }\text{ΔE°}\text{2Γ}$, where ΔE° is the energy difference between the two minima of the effective tunneling potential for the proton and Γ is the exchange (tunneling) integral. Furthermore, it was shown that the reduction in σ originates predominantly from the paramagnetic centers resulting from irradiation.