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【答案】应助回帖
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xiao2dao: 金币+5, ★★★★★最佳答案 2013-03-14 09:39:26
data for ICSD #9533
Coll Code 9533
Rec Date 1980/01/01
Mod Date 2006/04/01
Chem Name Potassium Niobate
Structured K (Nb O3)
Sum K1 Nb1 O3
ANX ABX3
D(calc) 4.62
Title Cubic-tetragonal-orthorhombic-rhombohedral ferroelectric transitions
in perovskite potassium niobate. Neutron powder profile refinement of
the structures
Author(s) Hewat, A.W.
Reference Journal of Physics C
(1973), 6, 2559-2572
Phase Transition
(1992), 38, 127-220
Unit Cell 3.971 5.692 5.719 90. 90. 90.
Vol 129.27
Z 2
Space Group A m m 2
SG Number 38
Cryst Sys orthorhombic
Pearson oS10
Wyckoff e b a2
R Value .0211
Red Cell A 3.971 4.034 4.034 90.271 90 89.999 64.633
Trans Red 1.000 0.000 0.000 / 0.000 0.500 -0.500 / 0.000 0.500 0.500
Comments Stable from 263 to 498 K (2nd ref., Tomaszewski), 498-708
K: P4mm
Neutron diffraction (powder)
The structure has been assigned a PDF number (calculated
powder diffraction data): 01-071-0946
The structure has been assigned a PDF number (experimental
powder diffraction data): 32-822
Temperature in Kelvin: 295
Structure type : BaTiO3(orh)
At least one temperature factor is implausible or
meaningless but agrees with the value given in the paper.
Atom # OX SITE x y z SOF H
K 1 +1 2 a 0 0 0.0138(71) 1. 0
Nb 1 +5 2 b 0.5 0 0.5 1. 0
O 1 -2 2 a 0 0 0.5364(10) 1. 0
O 2 -2 4 e 0.5 0.2476(9) 0.2842(9) 1. 0
Lbl Type B11 B22 B33 B12 B13 B23
K1 K1+ 0.52(11) 0.63(24) 0.71(36) 0 0 0
Nb1 Nb5+ 0.38(5) 0.33(11) 0.15(28) 0 0 0
O1 O2- 0.12(7) 0.63(20) 0.80(35) 0 0 0
O2 O2- 0.69(5) 0.47(12) 0.30(21) 0 0 0.14(12) |
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