Structural study of the incommensurately and lock-in phases of Rb2ZnCl4

Authors:

Hedoux, A.; Grebille, D.; Jaud, J.; Godefroy, G.

Journal:

Acta Cryst. B 45 370-378 (1989)

DOI:

https://doi.org/10.1107/S0108768189004787

B-IncStrDB ID: 832Ea3uix Entry date: 2010-11-08 Last revision: 2021-12-30

RbZnClL

Chemical data


Structural Formula Sum: Cl4 Rb2 Zn1 [ Help ]

Formula weight: 378.1 Da [ Help ]

Crystallographic data and experimental details


a: 7.230(5) Å [ Help ]

b: 12.608(9) Å [ Help ]

c: 9.199(7) Å [ Help ]

α: 90 ° [ Help ]

β: 90 ° [ Help ]

γ: 90 ° [ Help ]

Volume: 838.5(10) Å3 [ Help ]

Z: 4 [ Help ]

μ: 15.633 mm-1 [ Help ]

Cell measurement temperature: 115 K [ Help ]

Crystal system: orthorhombic [ Help ]

Superspace group name (WJJ): P:P 21 c n:-1 s -1 [ Help ]

Superspace group name: P21cn(00γ)0s0 [ Help ]

Symmetry operations of the superspace group: [ Help ]

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

Space group name (H-M): P 21 c n [ Help ]

Modulation dimension: 1 [ Help ]

Measured independent wave vectors: [ Help ]

Wave vector id q_x q_y q_z
1 0 0 0.333333

Refinement details


Refinement remarks: Commensurate structure refined within the superspace formalism. Global phase unknown. [ Help ]

Modulation functions description: Displacive modulation:Fourier series. 1st-order harmonics. [ Help ]

Structure factors calc. details: Gaussian integration [ Help ]

Nb. of observed reflections: 2280 [ Help ]

wR(obs): 0.0587 [ Help ]

Structural Information


Average Structure: [ Help ]

Atom site label Atom symbol Symmetry multiplicity Occupancy x y z Uiso/equiv ADP type
Rb1 Rb 4 1 0.2494 0.4059(1) 0.6289(1) 0.0289(11) Uani
Rb2 Rb 4 1 0.2424(7) 0.8191(1) 0.4876(1) 0.0153(8) Uani
Zn Zn 4 1 0.2446(8) 0.4216(1) 0.2228(1) 0.0779(9) Uani
Cl1 Cl 4 1 0.2407(12) 0.4206(2) -0.0194(2) 0.0220(21) Uani
Cl2 Cl 4 1 0.2440(9) 0.5841(2) 0.3232(2) 0.0169(20) Uani
Cl3 Cl 4 1 -0.0060(9) 0.3407(5) 0.3102(6) 0.0215(23) Uani
Cl4 Cl 4 1 0.4909(9) 0.3362(4) 0.3125(6) 0.0204(23) Uani

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 0 0.333333

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

Modulation code Atom site label Displacement axis Wave vector code
Rb1x1 Rb1 x 1
Rb1y1 Rb1 y 1
Rb1z1 Rb1 z 1
Rb2x1 Rb2 x 1
Rb2y1 Rb2 y 1
Rb2z1 Rb2 z 1
Znx1 Zn x 1
Zny1 Zn y 1
Znz1 Zn z 1
Cl1x1 Cl1 x 1
Cl1y1 Cl1 y 1
Cl1z1 Cl1 z 1
Cl2x1 Cl2 x 1
Cl2y1 Cl2 y 1
Cl2z1 Cl2 z 1
Cl3x1 Cl3 x 1
Cl3y1 Cl3 y 1
Cl3z1 Cl3 z 1
Cl4x1 Cl4 x 1
Cl4y1 Cl4 y 1
Cl4z1 Cl4 z 1

Displacive (translational) Fourier coefficients: [ Help ]

Modulation code Cosine coefficient Sine coefficient
Rb1x1 -0.0116 0.0123(3)
Rb1y1 0.0015(4) 0.0046(4)
Rb1z1 -0.0017(4) 0.0014(5)
Rb2x1 -0.0021(3) 0.0202(2)
Rb2y1 -0.0013(3) 0.0005(3)
Rb2z1 0.0012(4) -0.0012(4)
Znx1 0.0035(2) 0.0108(2)
Zny1 0.0005(4) -0.0021(3)
Znz1 -0.0003(5) 0.0014(5)
Cl1x1 0.0100(10) 0.0503(8)
Cl1y1 -0.0059(7) -0.0044(8)
Cl1z1 -0.0013(8) 0.0057(9)
Cl2x1 0.0647(6) 0.0086(10)
Cl2y1 0.0008(8) -0.0033(5)
Cl2z1 0.0004(10) 0.009(7)
Cl3x1 -0.0249(9) 0.0069(8)
Cl3y1 0.0341(7) -0.0018(5)
Cl3z1 0.0208(8) -0.0114(7)
Cl4x1 -0.0244(9) 0.0044(8)
Cl4y1 -0.0321(7) -0.0009(5)
Cl4z1 -0.0126(8) 0.0115(7)