The modulated average structure of mullite

Authors:

Birkenstock, Johannes; Petricek, Vaclav; Pedersen, Bjoern; Schneider, Hartmut; Fischer, Reinhard X.

Journal:

Acta Crystallographica, Section B 71 358-368 (2015)

DOI:

http://dx.doi.org/10.1107/S205252061500757X

B-IncStrDB ID: 11262E9iecH Entry date: 2015-06-01 Last revision: 2021-12-12

I

Chemical data


Structural Formula Sum: Al4.8 O9.6 Si1.2 [ Help ]

Formula weight: 316.8 Da [ Help ]

Crystallographic data and experimental details


Crystal system: orthorhombic [ Help ]

Superspace group name: Pbam(α01/2)0ss [ Help ]

Symmetry operations of the superspace group: [ Help ]

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

a: 7.5911 Å [ Help ]

b: 7.6924 Å [ Help ]

c: 2.8899 Å [ Help ]

α: 90 ° [ Help ]

β: 90 ° [ Help ]

γ: 90 ° [ Help ]

Volume: 168.7522 Å3 [ Help ]

Modulation dimension: 1 [ Help ]

Measured independent wave vectors: [ Help ]

Wave vector id q_x q_y q_z
1 0.313700 0.000000 0.500000

Z: 1 [ Help ]

Cell measurement temperature: 293 K [ Help ]

μ: 1.057 mm-1 [ Help ]

Absorption correction type: empirical [ Help ]

Minimum transmission factor: 0.7414 [ Help ]

Maximum transmission factor: 0.8306 [ Help ]

Refinement details


Total nb. of reflections: 1234 [ Help ]

Nb. of observed reflections: 772 [ Help ]

Intense reflections threshold: I>3σ(I) [ Help ]

Refinement based on: F [ Help ]

R(obs): 0.0277 [ Help ]

wR(obs): 0.0558 [ Help ]

R(all): 0.0461 [ Help ]

wR(all): 0.0572 [ Help ]

S(all): 3.01 [ Help ]

S(obs): 3.82 [ Help ]

Nb. of reflections: 1234 [ Help ]

Nb. of parameters: 106 [ Help ]

Number of constraints: 48 [ Help ]

Weighting scheme: sigma [ Help ]

Weighting scheme remarks: w=1/(σ2(F)+0.0001F2) [ Help ]

Δ/σ(max): 0.0320 [ Help ]

Δ/σ(mean): 0.0063 [ Help ]

Δρ(max): 0.39 e_Å-3 [ Help ]

Δρ(min): -0.50 e_Å-3 [ Help ]

Extinction method: B-C type 1 Gaussian isotropic (Becker & Coppens, 1974) [ Help ]

Extinction coefficient: 2000(200) [ 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
Al1 Al 0 0 0 Uani 0.00670(13) 2 1 d ? ? ?
Al2 Al 0.14887(5) 0.34028(4) 0.5 Uani 0.00720(13) 4 0.5 d ? ? ?
Si2 Si 0.14887(5) 0.34028(4) 0.5 Uani 0.00720(13) 4 0.2963 d ? ? ?
Al3 Al 0.2626(2) 0.2055(2) 0.5 Uani 0.0087(4) 4 0.2037 d ? ? ?
Si3 Si 0.2626(2) 0.2055(2) 0.5 Uani 0.0087(4) 4 0 d ? ? ?
O1 O 0.35820(9) 0.42264(10) 0.5 Uani 0.0132(2) 4 1 d ? ? ?
O2 O 0.12772(10) 0.21868(11) 0 Uani 0.0134(2) 4 1 d ? ? ?
O3 O 0 0.5 0.5 Uani 0.0198(16) 2 0.3889 d ? ? ?
O4 O 0.4523(8) 0.0457(11) 0.5 Uani 0.0119(17) 4 0.2037 d ? ? ?

ADP components: [ Help ]

Atom site label Atom site symbol U11 U22 U33 U12 U13 U23
Al1 Al 0.0079(2) 0.0068(2) 0.0054(2) 0.00073(11) 0 0
Al2 Al 0.0065(2) 0.0081(2) 0.0070(2) -0.00052(10) 0 0
Si2 Si 0.0065(2) 0.0081(2) 0.0070(2) -0.00052(10) 0 0
Al3 Al 0.0088(7) 0.0090(6) 0.0082(6) 0.0015(5) 0 0
Si3 Si 0.0088(7) 0.0090(6) 0.0082(6) 0.0015(5) 0 0
O1 O 0.0141(4) 0.0188(4) 0.0066(3) -0.0079(3) 0 0
O2 O 0.0156(3) 0.0136(4) 0.0109(3) -0.0063(2) 0 0
O3 O 0.007(3) 0.024(4) 0.0283(17) -0.0002(16) 0 0
O4 O 0.005(3) 0.017(4) 0.0138(18) -0.003(2) 0 0

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

Wave vector code q_1
1 1

Table: [ Help ]

_jana_atom_site_occ_Fourier_absolute_site_label _jana_atom_site_occ_Fourier_absolute
Al2 0.5
Si2 0.2963
Al3 0.2037
Si3 0
O3 0.3889
O4 0.2037

Definition of the occupation Fourier series: [ Help ]

Modulation code Atom site label Wave vector code
Al2o1 Al2 1
Si2o1 Si2 1
Al3o1 Al3 1
Si3o1 Si3 1
O3o1 O3 1
O4o1 O4 1

Occupation Fourier coefficients: [ Help ]

Modulation code Cosine coefficient Sine coefficient
Al2o1 0.0254(5) 0.00766(16)
Si2o1 0.0254(5) 0.00766(16)
Al3o1 -0.0207(6) -0.0144(6)
Si3o1 -0.0207(6) -0.0144(6)
O3o1 0.0265(5) 0
O4o1 -0.0140(6) -0.0210(6)

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

Modulation code Atom site label Displacement axis Wave vector code
Al1x1 Al1 x 1
Al1y1 Al1 y 1
Al1z1 Al1 z 1
Al2x1 Al2 x 1
Al2y1 Al2 y 1
Al2z1 Al2 z 1
Si2x1 Si2 x 1
Si2y1 Si2 y 1
S12z1 Si2 z 1
Al3x1 Al3 x 1
Al3y1 Al3 y 1
Al3z1 Al3 z 1
Si3x1 Si3 x 1
Si3y1 Si3 y 1
S13z1 Si3 z 1
O1x1 O1 x 1
O1y1 O1 y 1
O1z1 O1 z 1
O1x2 O2 x 1
O1y2 O2 y 1
O1z2 O2 z 1
O1x3 O3 x 1
O1y3 O3 y 1
O1z3 O3 z 1
O1x4 O4 x 1
O1y4 O4 y 1
O1z4 O4 z 1

Displacive (translational) Fourier coefficients: [ Help ]

Modulation code Cosine coefficient Sine coefficient
Al1x1 0 0
Al1y1 0 0
Al1z1 0 -0.00392(14)
Al2x1 0.00041(5) -0.00102(5)
Al2y1 -0.00023(5) -0.00112(5)
Al2z1 0 0
Si2x1 0.00041(5) -0.00102(5)
Si2y1 -0.00023(5) -0.00112(5)
S12z1 0 0
Al3x1 0.0008(3) -0.0001(2)
Al3y1 0.0005(2) -0.0009(2)
Al3z1 0 0
Si3x1 0.0008(3) -0.0001(2)
Si3y1 0.0005(2) -0.0009(2)
S13z1 0 0
O1x1 -0.00122(11) -0.00169(11)
O1y1 0.00270(9) 0.00192(10)
O1z1 0 0
O1x2 0 0
O1y2 0 0
O1z2 -0.0056(2) -0.0021(2)
O1x3 0 -0.0041(7)
O1y3 0 -0.0004(9)
O1z3 0 0
O1x4 -0.0018(12) 0.0044(8)
O1y4 -0.0080(16) -0.0028(8)
O1z4 0 0

Definition of the ADP Fourier series: [ Help ]

Modulation code Atom site label Tensor element Wave vector code
Al1U111 Al1 U11 1
Al1U221 Al1 U22 1
Al1U331 Al1 U33 1
Al1U121 Al1 U12 1
Al1U131 Al1 U13 1
Al1U231 Al1 U23 1
Al2U111 Al2 U11 1
Al2U221 Al2 U22 1
Al2U331 Al2 U33 1
Al2U121 Al2 U12 1
Al2U131 Al2 U13 1
Al2U231 Al2 U23 1
Si2U111 Si2 U11 1
Si2U221 Si2 U22 1
Si2U331 Si2 U33 1
Si2U121 Si2 U12 1
Si2U131 Si2 U13 1
Si2U231 Si2 U23 1
Al3U111 Al3 U11 1
Al3U221 Al3 U22 1
Al3U331 Al3 U33 1
Al3U121 Al3 U12 1
Al3U131 Al3 U13 1
Al3U231 Al3 U23 1
Si3U111 Si3 U11 1
Si3U221 Si3 U22 1
Si3U331 Si3 U33 1
Si3U121 Si3 U12 1
Si3U131 Si3 U13 1
Si3U231 Si3 U23 1
O1U111 O1 U11 1
O1U221 O1 U22 1
O1U331 O1 U33 1
O1U121 O1 U12 1
O1U131 O1 U13 1
O1U231 O1 U23 1
O2U111 O2 U11 1
O2U221 O2 U22 1
O2U331 O2 U33 1
O2U121 O2 U12 1
O2U131 O2 U13 1
O2U231 O2 U23 1
O3U111 O3 U11 1
O3U221 O3 U22 1
O3U331 O3 U33 1
O3U121 O3 U12 1
O3U131 O3 U13 1
O3U231 O3 U23 1
O4U111 O4 U11 1
O4U221 O4 U22 1
O4U331 O4 U33 1
O4U121 O4 U12 1
O4U131 O4 U13 1
O4U231 O4 U23 1

ADP Fourier coefficients: [ Help ]

Modulation code Cosine coefficient Sine coefficient
Al1U111 0 0
Al1U221 0 0
Al1U331 0 0
Al1U121 0 0
Al1U131 -0.00010(18) 0
Al1U231 -0.00051(17) 0
Al2U111 -0.0022(2) -0.0002(2)
Al2U221 -0.0019(2) 0.0008(2)
Al2U331 -0.00133(19) -0.00015(18)
Al2U121 -0.00014(18) -0.00030(16)
Al2U131 0 0
Al2U231 0 0
Si2U111 -0.0022(2) -0.0002(2)
Si2U221 -0.0019(2) 0.0008(2)
Si2U331 -0.00133(19) -0.00015(18)
Si2U121 -0.00014(18) -0.00030(16)
Si2U131 0 0
Si2U231 0 0
Al3U111 0.0099(10) 0.0025(10)
Al3U221 0.0082(9) 0.0046(10)
Al3U331 0.0092(9) 0.0049(8)
Al3U121 0.0011(7) -0.0007(7)
Al3U131 0 0
Al3U231 0 0
Si3U111 0.0099(10) 0.0025(10)
Si3U221 0.0082(9) 0.0046(10)
Si3U331 0.0092(9) 0.0049(8)
Si3U121 0.0011(7) -0.0007(7)
Si3U131 0 0
Si3U231 0 0
O1U111 -0.0019(5) -0.0009(4)
O1U221 -0.0001(4) 0.0003(5)
O1U331 0.0003(3) 0.0005(3)
O1U121 0.0014(4) 0.0005(4)
O1U131 0 0
O1U231 0 0
O2U111 0 0
O2U221 0 0
O2U331 0 0
O2U121 0 0
O2U131 -0.0003(3) -0.0006(3)
O2U231 -0.0001(3) 0.0009(3)
O3U111 0.010(5) 0
O3U221 -0.016(6) 0
O3U331 0.000(3) 0
O3U121 0.000(3) 0
O3U131 0 0
O3U231 0 0
O4U111 -0.002(4) 0.005(3)
O4U221 0.025(5) 0.008(3)
O4U331 0.004(3) 0.008(2)
O4U121 -0.010(3) -0.0025(19)
O4U131 0 0
O4U231 0 0

II

Chemical data


Structural Formula Sum: Al4.78 O9.61 Si1.22 [ Help ]

Formula weight: 317 Da [ Help ]

Crystallographic data and experimental details


Crystal system: orthorhombic [ Help ]

Space group name (H-M): P b a m [ Help ]

Space group name (Hall): -P -2xab;-2yab;-2z [ Help ]

Space group nb.: 55 [ Help ]

Symmetry operations of the space group: [ Help ]

Operation code Operation in algebraic form
1 x,y,z
2 -x,-y,z
3 -x+1/2,y+1/2,-z
4 x+1/2,-y+1/2,-z
5 -x,-y,-z
6 x,y,-z
7 x+1/2,-y+1/2,z
8 -x+1/2,y+1/2,z

a: 7.5757 Å [ Help ]

b: 7.6651 Å [ Help ]

c: 2.885 Å [ Help ]

α: 90 ° [ Help ]

β: 90 ° [ Help ]

γ: 90 ° [ Help ]

Volume: 167.5276 Å3 [ Help ]

Z: 1 [ Help ]

Cell measurement temperature: 293 K [ Help ]

μ: 0.00044 mm-1 [ Help ]

Minimum transmission factor: 0.997 [ Help ]

Maximum transmission factor: 0.998 [ Help ]

Refinement details


Total nb. of reflections: 1534 [ Help ]

Nb. of observed reflections: 1516 [ Help ]

Intense reflections threshold: I>3σ(I) [ Help ]

Refinement based on: F [ Help ]

R(obs): 0.0497 [ Help ]

wR(obs): 0.0668 [ Help ]

R(all): 0.0504 [ Help ]

wR(all): 0.0671 [ Help ]

S(all): 2.68 [ Help ]

S(obs): 2.68 [ Help ]

Nb. of reflections: 1534 [ Help ]

Nb. of parameters: 47 [ Help ]

Number of constraints: 16 [ Help ]

Weighting scheme: sigma [ Help ]

Weighting scheme remarks: w=1/(σ2(F)+0.0004F2) [ Help ]

Δ/σ(max): 0.0070 [ Help ]

Δ/σ(mean): 0.0010 [ Help ]

Δρ(max): 1.12 e_Å-3 [ Help ]

Δρ(min): -0.69 e_Å-3 [ Help ]

Extinction method: B-C type 1 Lorentzian anisotropic (Becker & Coppens, 1975) [ Help ]

Refinement remarks: The anisotropic components of the Type I extinction correction: -0.014(5) -0.026(2) -0.0078(8) -0.008(2) -0.001(1) -0.0009(7) [ 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
Al1 Al 0 0 0 Uani 0.0045(3) 2 1 d ? ? ?
Al2 Al 0.14897(9) 0.34022(13) 0.5 Uani 0.0049(3) 4 0.56(5) d ? ? ?
Si2 Si 0.14897(9) 0.34022(13) 0.5 Uani 0.0049(3) 4 0.24(5) d ? ? ?
Al3 Al 0.2619(4) 0.2066(4) 0.5 Uani 0.0054(9) 4 0.13(5) d ? ? ?
Si3 Si 0.2619(4) 0.2066(4) 0.5 Uani 0.0054(9) 4 0.06(5) d ? ? ?
O1 O 0.35845(5) 0.42238(8) 0.5 Uani 0.0111(2) 4 1 d ? ? ?
O2 O 0.12734(5) 0.21852(7) 0 Uani 0.0116(2) 4 1 d ? ? ?
O3 O 0.5 0 0.5 Uani 0.0194(16) 2 0.42(2) d ? ? ?
O4 O 0.4496(11) 0.0518(9) 0.5 Uani 0.0072(9) 4 0.195(8) d ? ? ?

ADP components: [ Help ]

Atom site label Atom site symbol U11 U22 U33 U12 U13 U23
Al1 Al 0.0056(4) 0.0065(4) 0.0013(5) 0.0011(3) 0 0
Al2 Al 0.0038(4) 0.0081(5) 0.0029(5) -0.0013(2) 0 0
Si2 Si 0.0038(4) 0.0081(5) 0.0029(5) -0.0013(2) 0 0
Al3 Al 0.0016(14) 0.0091(13) 0.0055(19) 0.0014(10) 0 0
Si3 Si 0.0016(14) 0.0091(13) 0.0055(19) 0.0014(10) 0 0
O1 O 0.0116(4) 0.0199(4) 0.0018(4) -0.00831(17) 0 0
O2 O 0.0131(3) 0.0138(4) 0.0078(4) -0.00698(15) 0 0
O3 O 0.018(3) 0.018(4) 0.0224(13) -0.006(3) 0 0
O4 O 0.0094(18) 0.0047(15) 0.0073(12) -0.0002(11) 0 0