A five-dimensional structure investigation of the misfit layer compound [Bi0.87SrO2]2[CoO2]1.82

Authors:

Leligny, H.; Grebille, D.; Perez, O.; Masset, A.C.; Hervieu, M.; Raveau, B.

Journal:

Acta Crystallographica, Section B 56 173-182 (2000)

DOI:

https://doi.org/10.1107/S0108768199012586

B-IncStrDB ID: 1212EU4Q3g Entry date: 2010-11-08 Last revision: 2022-02-15

comp1012814988

Chemical data


Structural Formula Sum: Bi1.74 Sr2 Co1.82 O7.64 [ Help ]

Crystallographic data and experimental details


Number of subsystems: 2 [ Help ]

Modulation dimension: 2 [ Help ]

a: 4.905(2) Å [ Help ]

b: 5.112(1) Å [ Help ]

c: 29.857(5) Å [ Help ]

γ: 90 ° [ Help ]

β: 93.45(2) ° [ Help ]

α: 90 ° [ Help ]

Z: 4 [ Help ]

Measured independent wave vectors: [ Help ]

Wave vector id q_x q_y q_z
1 0.293(2) 0 0.915(9)
2 0. 1.8204(5) 0

Subsystem code: 1 [ Help ]

Subsystem description: subsystem 1: [BiO] and [SrO] layers [ Help ]

W matrix:

1.0 0.0 0.0 0.0 0.0
0.0 1.0 0.0 0.0 0.0
0.0 0.0 1.0 0.0 0.0
0.0 0.0 0.0 1.0 0.0
0.0 0.0 0.0 0.0 1.0

Subsystem code: 2 [ Help ]

Subsystem description: subsystem 2: [CoO2] layers [ Help ]

W matrix:

1.0 0.0 0.0 0.0 0.0
0.0 0.0 0.0 0.0 1.0
0.0 0.0 1.0 0.0 0.0
0.0 0.0 0.0 1.0 0.0
0.0 1.0 0.0 0.0 0.0

Superspace group name: I2/a (α 0 γ, 0 μ 0) pmm [ Help ]

Symmetry operations of the superspace group: [ Help ]

Operation code Operation in algebraic form
1 x1,x2,x3,x4,x5
2 -x1,x2+1/2,-x3+1/2,-x4,x5
3 -x1,-x2,-x3,-x4,-x5
4 x1,-x2+1/2,x3+1/2,x4,-x5
5 x1+1/2,x2+1/2,x3+1/2,x4,x5
6 -x1+1/2,x2,-x3,-x4,x5
7 -x1+1/2,-x2+1/2,-x3+1/2,-x4,-x5
8 x1+1/2,-x2,x3,x4,-x5

Refinement details


Structural Information


Average Structure: [ Help ]

Atom site label Subsystem Occupancy x y z Uiso/equiv ADP type
Bi 1 0.868(2) 0.0197(3) 0.2638(1) 0.05357(3) 0.0158(1) Uani
Sr 1 1 0.0555(1) -0.2514(1) 0.14851(2) 0.0116(1) Uani
O1 1 1 0.0456(7) 0.2337(7) 0.1227(1) 0.0141(6) Uiso
O2 1 1 0.017(2) 0.6773(7) 0.0576(2) 0.026(1) Uiso
Co 2 1 0 0.25 0.25 0.0062(2) Uani
O3 2 1 -0.1787(5) 0.75 0.21651(7) 0.0084(5) Uiso

ADP components: [ Help ]

Atom site label U11 U22 U33 U12 U13 U23
Bi 0.0210(2) 0.0167(2) 0.0096(1) 0 0.0007(2) 0.0006(3)
Sr 0.0093(2) 0.0146(2) 0.0109(2) 0 0.0014(2) 0
Co 0.0008(3) 0.0075(6) 0.0102(3) 0 0.0005(2) 0

Fourier Wave Vectors (explicit: q_x,q_y,q_z or coefficients: q_1,q_2,...): [ Help ]

Wave vector code q_x q_y q_z
1 0.293 0 0.915
2 0.586 0 1.830

Definition of the displacive (translational) Fourier series: [ Help ]

Modulation code Atom site label Displacement axis Wave vector code
Bix1 Bi x 1
Bix2 Bi x 2
Biy1 Bi y 1
Biy2 Bi y 2
Biz1 Bi z 1
Biz2 Bi z 2
Srx1 Sr x 1
Sry1 Sr y 1
Srz1 Sr z 1
O1x1 O1 x 1
O1y1 O1 y 1
O1z1 O1 z 1
O2x1 O2 x 1
O2y1 O2 y 1
O2z1 O2 z 1

Displacive (translational) Fourier coefficients: [ Help ]

Modulation code Sine coefficient Cosine coefficient
Bix1 0.0062(4) -0.0020(3)
Bix2 0 0.0000(0)
Biy1 -0.0010(4) 0.0004(3)
Biy2 0 -0.0052(5)
Biz1 0.00018(2) 0.00055(3)
Biz2 0 0
Srx1 -0.0025(2) 0.0043(2)
Sry1 0 0
Srz1 0.00132(4) 0.0073(4)
O1x1 -0.004(2) 0.008(2)
O1y1 0 0
O1z1 0.0006(3) 0.0012(3)
O2x1 -0.007(6) 0.006(3)
O2y1 0 0
O2z1 0.0016(4) 0.0021(5)

Displacive sawtooth coefficients: [ Help ]

Atom site label Ax Center (x0) Width
Bi 0.0830(6) 0.551(2) 1.0
O2 0.046(7) 0 1.0

Definition of the occupation Fourier series: [ Help ]

Modulation code Atom site label Wave vector code
Bio1 Bi 1
Bio2 Bi 2

Occupation Fourier coefficients: [ Help ]

Modulation code Sine coefficient Cosine coefficient
Bio1 -0.082(2) -0.208(2)
Bio2 -0.098(3) -0.116(3)

Definition of the ADP Fourier series: [ Help ]

Modulation code Atom site label Tensor element Wave vector code
BiU111 Bi U11 1
BiU221 Bi U22 1
BiU331 Bi U33 1
BiU121 Bi U12 1
BiU131 Bi U13 1
BiU231 Bi U23 1

ADP Fourier coefficients: [ Help ]

Modulation code Sine coefficient Cosine coefficient
BiU111 0.0027(3) 0.0069(4)
BiU221 0.0027(3) 0.0057(4)
BiU331 0.0010(3) 0.0004(3)
BiU121 -0.0028(3) 0
BiU131 0.0006(2) -0.0005(3)
BiU231 0.0013(4) 0.0047(9)