Incommensurately Modulated Crystal Structure of α' (O'3)-type Sodium Cobalt Oxide NaxCoO2 (x ∼ 0.78)

Authors:

Miyazaki, Yuzuru; Igawa, Naoki; Yubuta, Kunio

Journal:

Acta Crystallographica Section B 77 371-377 (2021)

DOI:

https://doi.org/10.1107/S205252062100370X

B-IncStrDB ID: 16942E6CXxJ Entry date: 2022-01-10 Last revision: 2022-01-25

I

Chemical data


Structural Formula Sum: Na0.779 Co1 O2 [ Help ]

Formula weight: 108.84 Da [ Help ]

Crystallographic data and experimental details


Crystal system: monoclinic [ Help ]

Superspace group name: C2/m(α0γ)00 [ Help ]

Symmetry operations of the superspace group: [ Help ]

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

a: 4.88979(17) Å [ Help ]

b: 2.86782(8) Å [ Help ]

c: 5.78034(19) Å [ Help ]

α: 90 ° [ Help ]

β: 111.8897(16) ° [ Help ]

γ: 90 ° [ Help ]

Volume: 75.214(4) Å3 [ Help ]

Modulation dimension: 1 [ Help ]

Measured independent wave vectors: [ Help ]

Wave vector id q_x q_y q_z
1 0.3458(3) 0.000000 -0.2624(3)

Z: 2 [ Help ]

Cell measurement temperature: 293 K [ Help ]

μ: 0.101 mm-1 [ Help ]

Refinement details


R(obs): 0.0303 [ Help ]

wR(obs): 0.0344 [ Help ]

R(all): 0.0329 [ Help ]

wR(all): 0.0347 [ Help ]

S(all): 1.81 [ Help ]

Nb. of parameters: 42 [ Help ]

Number of restraints: 0 [ Help ]

Number of constraints: 0 [ Help ]

Weighting scheme: sigma [ Help ]

Δ/σ(max): 0.0487 [ Help ]

Δ/σ(mean): 0.0146 [ Help ]

Structural Information


Average Structure: [ Help ]

Atom site label Atom symbol x y z ADP type Uiso/equiv Symmetry multiplicity Occupancy Coords from (d)iffraction or (c)alculated Coords restraints or constraints Disordered cluster Disordered group
Na Na 0 0.5 0.5 Uiso 0.0086(13) 4 0.5 d . . .
Co Co 0 0 0 Uiso 0.0110(9) 2 1 d . . .
O O 0.2544(3) 0 0.8162(2) Uiso 0.0104(4) 4 1 d . . .

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

Wave vector code q_1
1 1
2 2

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

Modulation code Atom site label Displacement axis Wave vector code
Nax1 Na x 1
Nay1 Na y 1
Naz1 Na z 1
Nax2 Na x 2
Nay2 Na y 2
Naz2 Na z 2
Cox1 Co x 1
Coy1 Co y 1
Coz1 Co z 1
Cox2 Co x 2
Coy2 Co y 2
Coz2 Co z 2
Ox1 O x 1
Oy1 O y 1
Oz1 O z 1
Ox2 O x 2
Oy2 O y 2
Oz2 O z 2

Displacive (translational) Fourier coefficients: [ Help ]

Modulation code Cosine coefficient Sine coefficient
Nax1 0 -0.040(5)
Nay1 0 0
Naz1 0 0.043(4)
Nax2 0 0
Nay2 0 0
Naz2 0 0
Cox1 0 0.0309(15)
Coy1 0 0
Coz1 0 0.0500(12)
Cox2 0 0.005(3)
Coy2 0 0
Coz2 0 -0.004(2)
Ox1 0.0175(5) 0.0308(4)
Oy1 0 0
Oz1 -0.0058(5) 0.0508(3)
Ox2 0.0032(10) -0.0048(9)
Oy2 0 0
Oz2 0.0024(7) -0.0024(5)

Displacive sawtooth coefficients: [ Help ]

Atom site label Ax Ay Az Center (x0) Width
Na 0.234(7) 0 -0.013(5) 0.051(4) 0.779(6)