Lns-Mossbauer and lattice parameter data of DF oxides

In oxides, the IS(Eu ) is known to correlate well with the average BL(Eu —O) (and CN) of the system that the 

This gives a reference point to fix the BL(Eu we found a C-type line phase at y y=6/7 = 0.857 [29]. But its C-type structure implies the possibility that a partially oxidized C-type yS+,6+gij3+ Q (z 0) is formed there. 

Zr-Gd has many unique properties, such as the second a(ion)(max) in the ideal P Gd2Zr207 at y=0.50 [32] that diminishes by a factor of 1/5 by the P DF disordering treatment above Ta-= I530°C [41] and the high radiation 

QS(24d-Gd +) 5.6 QS(8b-Gd ) 10.9. Such well-separated two-site QS behavior of C GdOi.s was reproduced with the point-charge model (PCM) QS calculation in Refs. 46 and 19b. 

This means that the minor Sb-Gd has much more distorted Gd +(VI)—60 octahedron than the major 24d-Gd + in Fig. 4.1b both from the present Gd Mossbauer and distortional-dilation viewpoint [1—4]. However, whether the more distorted former has indeed more dilated BL(Gd —60) too, that is, BL(Gd +(8b)—O) BL(Gd (24d)—O), needs more careful examination of XRD structure data of various C LnO 5S [I8c,47—49], for, as listed in Table 4.1, in both C GdOi. 5 and EuO 5 the reverse possibility of BL(Ln (24d)—O) BL(Ln (8b)—O) cannot be excluded. However, it appears much more certain in Table 4.1 that the overall average XRD BL(Ln —0)s for the total 24d- -8b Ln s are longer than those calculated as the Shannon s rc(Ln (VI)) + ra(0 ) for the three systems also including YO1.5. This fact implies that different from the above Vo-free cubic F-type U-Eu (CN = 8) in Eq. (4.10), the macroscopic oq distortional-dilation of defective C-type LnOi. 5 (/c fi= in Fig. 4.2a) has indeed its coupled microscopic BL(Ln —O) and rc(Ln ) distortional-dilation, that is, rc(Ln (VI))(XRD rc(Ln (VI))(Shannon). This has also much 

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