Here are the ICSD entries for Na2CO3:
(by the way, the ICSD costs only 500 US dollars per year).
COL ICSD Collection Code 81013
DATE Recorded May 13, 1997
NAME Sodium carbonate - alpha
FORM Na2 (C O3)
= C Na2 O3
TITL Neutron powder diffraction study of the ferroelastic phase
transition and lattice melting in sodium carbonate, Na2 C O3
REF Journal of Physics: Condensed Matter
JCOME 7 (1995) 4395-4417
AUT Swainson I P, DoveÿMÿT, HarrisÿMÿJ
CELL a=5.213 b=5.213 c=6.676 à=90.0 á=90.0 ç=120.0
V=157.1 Z=2
SGR P 63/m m c (194) - hexagonal
CLAS 6/mmm (Hermann-Mauguin) - D6h (Schoenflies)
PRS hP12
ANX AB2X3
PARM Atom__No OxStat Wyck -----X----- -----Y----- -----Z----- -SOF-
Na 1 1.000 2a 0. 0. 0.
Na 2 1.000 2c 2/3 1/3 3/4
C 1 4.000 2d 2/3 1/3 1/4
O 1 -2.000 6h 0.7964 0.2036 1/4
WYCK h d c a
REM TEM 972
REM NDP (neutron diffraction from a powder)
REM RVP
TEST No R value given in the paper. (Code 51)
TEST At least one temperature factor missing in the paper. (Code
53)
COL ICSD Collection Code 12168
DATE Recorded Jan 1, 1980; updated Jun 29, 1998
NAME Sodium carbonate
MINR Natrite high
FORM Na2 (C O3)
= C Na2 O3
TITL Disordered structure of Na2 C O3 at 400 C
REF Physica B and C (Netherland) (79,1975- 151,1987)
PHBCD 96 (1979) 89-95
AUT de Pater C J
CELL a=9.013(2) b=5.237(2) c=6.312(2) à=90.0 á=96.8(0) ç=90.0
V=295.8 Z=4
SGR C 1 2/m 1 (12) - monoclinic
CLAS 2/m (Hermann-Mauguin) - C2h (Schoenflies)
PRS mC24
ANX AB2X3
PARM Atom__No OxStat Wyck -----X----- -----Y----- -----Z----- -SOF-
Na 1 1.000 2a 0. 0. 0.
Na 2 1.000 2c 0. 0. 1/2
Na 3 1.000 4i 0.167(5) 1/2 0.755(5)
C 1 4.000 4i 0.163(5) 1/2 0.251(3)
O 1 -2.000 8j 0.104(1) 0.303(3) 0.275(5)
O 2 -2.000 4i 0.283(5) 1/2 0.198(5)
WYCK j i3 c a
ITF Na 1 U=0.09
ITF Na 2 U=0.09
ITF Na 3 U=0.09
ITF C 1 U=0.09
ITF O 1 U=0.09
ITF O 2 U=0.09
REM TEM 673
RVAL 0.050
TEST At least one temperature factor missing in the paper. (Code
53)
COL ICSD Collection Code 16024
DATE Recorded Jan 1, 1980; updated Jun 29, 1998
NAME Sodium carbonate - gamma
MINR Natrite - synthetic
FORM Na2 (C O3)
= C Na2 O3
TITL The average crystal structure of gamma Na2 C O3
REF Acta Crystallographica B (24,1968-38,1982)
ACBCA 25 (1969) 2665-2667
AUT Dubbeldam G C, de WolffÿPÿM
CELL a=8.900 b=5.240 c=6.040 à=90.0 á=101.2 ç=90.0
V=276.3 D=2.54 Z=4
SGR C 1 2/m 1 (12) - monoclinic
CLAS 2/m (Hermann-Mauguin) - C2h (Schoenflies)
PRS mC24
ANX AB2X3
PARM Atom__No OxStat Wyck -----X----- -----Y----- -----Z----- -SOF-
Na 1 1.000 4g 0. 0.018 0. 0.5
Na 2 1.000 4h 0. 0.022 1/2 0.5
Na 3 1.000 8j 0.172 0.544 0.749 0.5
C 1 4.000 8j 0.163 0.488 0.251 0.5
O 1 -2.000 8j 0.123 0.255 0.314 0.5
O 2 -2.000 8j 0.291 0.491 0.173 0.5
O 3 -2.000 8j 0.079 0.676 0.255 0.5
WYCK j5 h g
REM M PDF 37-451, averaged structure, structure is modulated,
cp. 60311
RVAL 0.128
TEST Calculated density unusual but tolerable. (Code 23)
TEST At least one temperature factor missing in the paper. (Code
53)
COL ICSD Collection Code 60311
DATE Recorded Apr 15, 1986; updated Jun 29, 1998
NAME Sodium carbonate - gamma
MINR Natrite
FORM Na2 (C O3)
= C Na2 O3
TITL The modulated structure of gamma Na2 C O3 in a harmonic
approximation
REF Acta Crystallographica B (24,1968-38,1982)
ACBCA 32 (1976) 47-58
REF Acta Crystallographica B (24,1968-38,1982)
ACBCA 25 (1969) 2665-2667
AUT van Aalst W, den HollanderÿJ, PeterseÿWÿJÿAÿM, de
WolffÿPÿM
CELL a=8.904(3) b=5.239(2) c=6.042(2) à=90.0 á=101.3(0) ç=90.0
V=276.3 D=2.54 Z=4
SGR C 1 2/m 1 (12) - monoclinic
CLAS 2/m (Hermann-Mauguin) - C2h (Schoenflies)
PRS mC24
ANX AB2X3
PARM Atom__No OxStat Wyck -----X----- -----Y----- -----Z----- -SOF-
Na 1 1.000 2a 0. 0. 0.
Na 2 1.000 2c 0. 0. 1/2
Na 3 1.000 4i 0.1760(1) 1/2 0.7478(2)
C 1 4.000 4i 0.1641(2) 1/2 0.2496(3)
O 1 -2.000 4i 0.2897(2) 1/2 0.1771(3)
O 2 -2.000 8j 0.1016(2) 0.2940(3) 0.2855(2)
WYCK j i3 c a
ÿ
TF Atom á(1,1) á(2,2) á(3,3) á(1,2) á(1,3) á(2,3)
Na 1 0.0039 0.0122 0.0079 0.0000 0.0020 0.0000
(1) (5) (3) (1)
Na 2 0.0042 0.0074 0.0080 0.0000 0.0230 0.0000
(1) (5) (3) (10)
Na 3 0.0050 0.0148 0.0157 0.0000 0.0030 0.0000
(1) (4) (3) (1)
C 1 0.0025 0.0073 0.0059 0.0000 0.0010 0.0000
(1) (6) (4) (2)
O 1 0.0031 0.0190 0.0115 0.0000 0.0035 0.0000
(1) (6) (3) (2)
O 2 0.0058 0.0093 0.0135 0.0014 0.0020 -0.0008
(2) (7) (3) (4) (2) (4)
REM MOD (modulated/incommensurate structure)
REM M PDF 37-451
RVAL 0.108
TEST Calculated density unusual but tolerable. (Code 23)
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Dr. Uwe Kolitsch
Institut für Mineralogie und Kristallographie
Geozentrum
Universität Wien
Althanstr. 14
A-1090 Wien
Austria
Tel +43-1-4277-53239
Fax +43-1-4277-9532
e-mail: [EMAIL PROTECTED]
home page: http://www.univie.ac.at/mineralogie/kolitsch.htm
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