Download - New observation of phase transition sequence in NBT

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Page 1: New observation of phase transition sequence in  NBT

New observation of phase transition sequence in NBT

2theta

8.55 8.6 8.65

0

50000

2theta

12.15 12.2 12.25

-10000

0

10000

20000

2theta

10.5 10.55 10.6

0

10000

2theta

9.6 9.8 10 10.2

-1000

-500

0

Temp (ºC)

Space group

Phase Frac.

a (Å) b (Å) c (Å) β (º) Fit Values

25 Cc 73% 9.526889 5.482203 5.508492 125.3630 Rp = 4.97%wRp = 6.87%Pm-3m 27% 3.885003 3.885003 3.885003 90

100 Cc 38% 9.521845 5.486220 5.5130 125.2941 Rp = 4.67%wRp = 6.20%Pm-3m 62% 3.887351 3.887351 3.887351 90

250 Cc 13% 9.53996 5.500718 5.513608 125.2970 Rp = 3.95%wRp = 5.01%Pm-3m 87% 3.893460 3.893460 3.893460 90

300 P4bm - 5.507792 5.507792 3.899572 90 Rp = 4.06%wRp = 5.11%

400 P4bm - 5.515262 5.515262 3.905851 90 Rp = 3.91%wRp = 4.90%

600 Pm-3m - 3.912135 3.912135 3.912135 90 Rp = 4.24%wRp = 5.70%

Pm-3mCc

600ºC 400ºC300ºC250ºC100ºC25ºC

110 111 200

½(310) ½(311)

110 111 200½(311)

High Resolution Diffraction Rietveld refinement of 250ºC Pattern