**Acknowledgements**

*Electron Crystallography*

NaCl:Li+

NaCl:K+

NaCl:Rb+

NaCl:Cs+

*Values of energy* G*0.*

**Table 1.**

where *k* is the Boltzmann constant and *T* is the absolute temperature.

*Variation of the interaction energy (*G*0) between dislocation and the dopant ion with the defect size* 

**Specimen** *G***0 (eV)**

(0.5 mol%) 0.55

(0.5 mol%) 0.60

(0.5 mol%) 0.61

(0.5 mol%) 0.82

NaCl:F<sup>−</sup> (0.5 mol%) 0.69 NaCl:Br<sup>−</sup> (0.5 mol%) 0.47 NaCl:I<sup>−</sup> (0.5 mol%) 0.53

∂τ ) in Eq. (1) is obtained from *λ*p. Eq. (1) is namely replaced by *V* = *kT*/ λp. (2)

ion. The *τ*p vs. *V* curve gives the value of *G*0 for the specimen.

, K+ , Cs+

, Br<sup>−</sup>, I<sup>−</sup>, F<sup>−</sup>, Br<sup>−</sup> or I<sup>−</sup> single crystals.

, F<sup>−</sup>, Br<sup>−</sup> or I<sup>−</sup>) are

This dependence (*τ*p vs. *V*) also represents the force-distance profile between

**Figure 7** shows the obtained energies *G*0 with the isotropic defect size (), which is estimated from the difference between the lattice constants of host crystal and dopant, around ion doped in the each specimen. The ions beside each plot represent the dopants in NaCl single crystals. *G*0 values vary linearly with in the specimens. The intercept of the straight line is 0.36 eV, which is considered to be the interaction energy between dislocation and inherent obstacle of the host crystal

The following conclusions were derived from the data analyzed in terms of the

, Cs+

**96**

Here, the (

**Figure 7.**

dislocation and Rb+

because is zero.

**6. Conclusions**

Δ*τ* vs. *λ* curves for NaCl: Li+

\_∂ ln ε̇

The *G*0 values for the other specimens (i.e. NaCl: Li+

*(reproduced from Ref. [58] with permission from the publisher).*

, K+ , Rb+

similarly estimated and are listed in **Table 1**.

Dr. T. Ohgaku, as well as S. Yamaguchi, M. Azuma, H. Teraji, E. Ogawa and Y. Yamanaka are acknowledged for his collaboration in the analysis on Δ*τ* and *λ* data, as well as for their experimental assistance.
