Structural phase transitions in polyphenyls. VIII. The modulated structure of phase III of biphenyl (T=20K) from neutron diffraction data
Authors:Baudour, J.L.; Sanquer, M.
Journal:Acta Cryst. B 39 75-84 (1983)
DOI:https://doi.org/10.1107/S0108768183002049
B-IncStrDB ID: 392EAYjQc Entry date: 2010-11-08 Last revision: 2022-02-11
biphenyl
Chemical data
Structural Formula Sum: C12 H10 [ Help ]
Formula weight: 154.2 Da [ Help ]
Common Name: Biphenyl [ Help ]
Crystallographic data and experimental details
a: 7.77(2) Å [ Help ]
b: 5.57(1) Å [ Help ]
c: 9.44(2) Å [ Help ]
α: 90 ° [ Help ]
β: 93.7(2) ° [ Help ]
γ: 90 ° [ Help ]
Volume: 407.7(15) Å3 [ Help ]
Z: 2 [ Help ]
Cell measurement temperature: 20 K [ Help ]
Crystal system: monoclinic [ Help ]
Superspace group name (WJJ): P:P a:-1 [ Help ]
Superspace group name: Pa(0β0)0 [ Help ]
Symmetry operations of the superspace group: (Show/hide table) [ Help ]
| Operation code | Operation in algebraic form |
|---|---|
| 1 | x1,x2,x3,x4 |
| 2 | 1/2+x1,-x2,x3,-x4 |
Space group name (H-M): P 1 a 1 [ Help ]
Modulation dimension: 1 [ Help ]
Measured independent wave vectors: (Show/hide table) [ Help ]
| Wave vector id | q_x | q_y | q_z |
|---|---|---|---|
| 1 | 0 | 0.46 | 0 |
Refinement details
Refinement remarks: The phenyl rings were considered as rigid blocks. Phenyl rings are related by a centre of inversion at (0,-1/4,0). WARNING: The published thermal displacement parameters, Biso, have been converted to Uiso. [ Help ]
Modulation functions description: Displacive modulation:Fourier series. 1st-order harmonics. [ Help ]
Structure factors calc. details: Bessel functions [ Help ]
Nb. of observed reflections: 538 [ Help ]
R(all): 0.106 [ Help ]
Structural Information
Average Structure: (Show/hide table) [ Help ]
| Site description | Atom site label | Atom symbol | Symmetry multiplicity | Occupancy | x | y | z | Uiso/equiv | ADP type |
|---|---|---|---|---|---|---|---|---|---|
| Rigid phenyl ring 1 | Phenyl1 | . | 2 | 0 | 0.103134 | -0.255728 | 0.222013 | . | . |
| . | C(1) | C | 2 | 1 | 0.0351 | -0.2518 | 0.0756 | 0.012(1) | Uiso |
| . | C(2) | C | 2 | 1 | -0.0052 | -0.0708 | 0.1704 | 0.016(1) | Uiso |
| . | C(3) | C | 2 | 1 | 0.0602 | -0.0746 | 0.3109 | 0.016(1) | Uiso |
| . | C(4) | C | 2 | 1 | 0.1674 | -0.2594 | 0.3604 | 0.010(1) | Uiso |
| . | C(5) | C | 2 | 1 | 0.2087 | -0.4404 | 0.2677 | 0.011(1) | Uiso |
| . | C(6) | C | 2 | 1 | 0.1433 | -0.4368 | 0.1271 | 0.009(1) | Uiso |
| . | D(7) | H | 2 | 1 | -0.0905 | 0.0770 | 0.1319 | 0.027(2) | Uiso |
| . | D(8) | H | 2 | 1 | 0.0266 | 0.0702 | 0.3842 | 0.024(2) | Uiso |
| . | D(9) | H | 2 | 1 | 0.2194 | -0.2624 | 0.4721 | 0.017(1) | Uiso |
| . | D(10) | H | 2 | 1 | 0.2941 | -0.5884 | 0.3061 | 0.025(2) | Uiso |
| . | D(11) | H | 2 | 1 | 0.1769 | -0.5818 | 0.0538 | 0.022(2) | Uiso |
| Rigid phenyl ring 2 | Phenyl2 | . | 2 | 0 | -0.103134 | -0.243805 | -0.222013 | . | . |
| . | C'(1) | C | 2 | 1 | -0.0351 | -0.2452 | -0.0756 | 0.012(1) | Uiso |
| . | C'(2) | C | 2 | 1 | 0.0052 | -0.4292 | -0.1704 | 0.016(1) | Uiso |
| . | C'(3) | C | 2 | 1 | -0.0602 | -0.4254 | -0.3109 | 0.016(1) | Uiso |
| . | C'(4) | C | 2 | 1 | -0.1674 | -0.2406 | -0.3604 | 0.010(1) | Uiso |
| . | C'(5) | C | 2 | 1 | -0.2087 | -0.0596 | -0.2677 | 0.011(1) | Uiso |
| . | C'(6) | C | 2 | 1 | -0.1433 | -0.0632 | -0.1271 | 0.009(1) | Uiso |
| . | D'(7) | H | 2 | 1 | 0.0905 | -0.5770 | -0.1319 | 0.027(2) | Uiso |
| . | D'(8) | H | 2 | 1 | -0.0266 | -0.5702 | -0.3842 | 0.024(2) | Uiso |
| . | D'(9) | H | 2 | 1 | -0.2194 | -0.2376 | -0.4721 | 0.017(1) | Uiso |
| . | D'(10) | H | 2 | 1 | -0.2941 | 0.0884 | -0.3061 | 0.025(2) | Uiso |
| . | D'(11) | H | 2 | 1 | -0.1769 | 0.0818 | -0.0538 | 0.022(2) | Uiso |
Fourier Wave Vectors (explicit: q_x,q_y,q_z or coefficients: q_1,q_2,...): (Show/hide table) [ Help ]
| Wave vector code | q_x | q_y | q_z |
|---|---|---|---|
| 1 | 0 | 0.46 | 0 |
_atom_sites_displace_Fourier_axes_description: a1 and a2 are respectively the long molecular axis and the axis normal to the mean molecular plane. [ Help ]