*data for ICSD #16593
Coll Code 16593
Rec Date 1980/01/01
Mod Date 1997/11/10
Chem Name Iron Carbide (3/1)
Structured Fe3 C
Sum C1 Fe3
ANX NO3
Min Name Cohenite
D(calc) 7.67
Title Comparison of X-ray and neutron-diffraction refinements of the
structure of cementite Fe3 C
Author(s) Herbstein, F.H.;Smuts, J.
Reference Acta Crystallographica (1,1948-23,1967)
(1964), 17, 1331-1332
Unit Cell 5.09 6.748 4.523 90. 90. 90.
Vol 155.35
Z 4
Space Group P n m a
SG Number 62
Cryst Sys orthorhombic
Pearson oP16
Wyckoff d c2
R Value .044
Red Cell P 4.523 5.09 6.748 90 90 90 155.353
Trans Red 0.000 0.000 1.000 / 1.000 0.000 0.000 / 0.000 1.000 0.000
Comments Compound with mineral name: Cohenite
The structure has been assigned a PDF number: 34-1
New refinement based on previously measured intensities
Structure type : Fe3C
X-ray diffraction (powder)
At least one temperature factor missing in the paper.
Atom # OX SITE x y z SOF H
Fe 1 +0 8 d 0.186(2) 0.063(2) 0.328(2) 1. 0
Fe 2 +0 4 c 0.036(2) 0.25 0.852(4) 1. 0
C 1 +0 4 c 0.89(2) 0.25 0.45(1) 1. 0
*end for ICSD #16593
*data for ICSD #44354
Coll Code 44354
Rec Date 2000/07/15
Chem Name Iron Carbide (3/1) - Epsilon
Structured Fe3 C
Sum C1 Fe3
ANX NO3
D(calc) 6.96
Title Study of metallic carbides by electron diffraction. Part III. Iron
carbides
Author(s) Nagakura, S.
Reference Journal of the Physical Society of Japan
(1959), 14, 186-195
Unit Cell 4.767 4.767 4.354 90. 90. 120.
Vol 85.69
Z 2
Space Group P 63 2 2
SG Number 182
Cryst Sys hexagonal
Pearson hP8
Wyckoff g d c
Red Cell P 4.354 4.767 4.767 120 90 90 85.686
Trans Red 0.000 0.000 1.000 / 1.000 0.000 0.000 / 0.000 1.000 0.000
Comments Thin layers
PDF 36-1249 (Fe2 C)
Total SOF on at least one site differs from unity (SOF <
0.997 resp. SOF > 1.003)
The structure has been assigned a PDF number: 36-1249
X-ray diffraction (powder)
No R value given in the paper.
At least one temperature factor missing in the paper.
Atom # OX SITE x y z SOF H
Fe 1 +0 6 g 0.3333 0 0 1. 0
C 1 +0 2 c 0.3333 0.6667 0.25 0.5 0
C 2 +0 2 d 0.3333 0.6667 0.75 0.5 0
*end for ICSD #44354,
*data for ICSD #16593
Coll Code 16593
Rec Date 1980/01/01
Mod Date 1997/11/10
Chem Name Iron Carbide (3/1)
Structured Fe3 C
Sum C1 Fe3
ANX NO3
Min Name Cohenite
D(calc) 7.67
Title Comparison of X-ray and neutron-diffraction refinements of the
structure of cementite Fe3 C
Author(s) Herbstein, F.H.;Smuts, J.
Reference Acta Crystallographica (1,1948-23,1967)
(1964), 17, 1331-1332
Unit Cell 5.09 6.748 4.523 90. 90. 90.
Vol 155.35
Z 4
Space Group P n m a
SG Number 62
Cryst Sys orthorhombic
Pearson oP16
Wyckoff d c2
R Value .044
Red Cell P 4.523 5.09 6.748 90 90 90 155.353
Trans Red 0.000 0.000 1.000 / 1.000 0.000 0.000 / 0.000 1.000 0.000
Comments Compound with mineral name: Cohenite
The structure has been assigned a PDF number: 34-1
New refinement based on previously measured intensities
Structure type : Fe3C
X-ray diffraction (powder)
At least one temperature factor missing in the paper.
Atom # OX SITE x y z SOF H
Fe 1 +0 8 d 0.186(2) 0.063(2) 0.328(2) 1. 0
Fe 2 +0 4 c 0.036(2) 0.25 0.852(4) 1. 0
C 1 +0 4 c 0.89(2) 0.25 0.45(1) 1. 0
*end for ICSD #16593
*data for ICSD #44354
Coll Code 44354
Rec Date 2000/07/15
Chem Name Iron Carbide (3/1) - Epsilon
Structured Fe3 C
Sum C1 Fe3
ANX NO3
D(calc) 6.96
Title Study of metallic carbides by electron diffraction. Part III. Iron
carbides
Author(s) Nagakura, S.
Reference Journal of the Physical Society of Japan
(1959), 14, 186-195
Unit Cell 4.767 4.767 4.354 90. 90. 120.
Vol 85.69
Z 2
Space Group P 63 2 2
SG Number 182
Cryst Sys hexagonal
Pearson hP8
Wyckoff g d c
Red Cell P 4.354 4.767 4.767 120 90 90 85.686
Trans Red 0.000 0.000 1.000 / 1.000 0.000 0.000 / 0.000 1.000 0.000
Comments Thin layers
PDF 36-1249 (Fe2 C)
Total SOF on at least one site differs from unity (SOF <
0.997 resp. SOF > 1.003)
The structure has been assigned a PDF number: 36-1249
X-ray diffraction (powder)
No R value given in the paper.
At least one temperature factor missing in the paper.
Atom # OX SITE x y z SOF H
Fe 1 +0 6 g 0.3333 0 0 1. 0
C 1 +0 2 c 0.3333 0.6667 0.25 0.5 0
C 2 +0 2 d 0.3333 0.6667 0.75 0.5 0
*end for ICSD #44354,
应该差不多,谢谢