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Information card for entry 2018308
Preview
| Coordinates | 2018308.cif |
|---|---|
| Structure factors | 2018308.hkl |
| Original IUCr paper | HTML |
| External links | ChemSpider |
| Chemical name | 3,7-dihydro-1,3-dimethyl-1<i>H</i>-purine-2,6-dione |
|---|---|
| Formula | C7 H8 N4 O2 |
| Calculated formula | C7 H8 N4 O2 |
| SMILES | c1nc2c(C(=O)N(C(=O)N2C)C)[nH]1 |
| Title of publication | Polymorphs of anhydrous theophylline: stable form IV consists of dimer pairs and metastable form I consists of hydrogen-bonded chains |
| Authors of publication | Khamar, Dikshitkumar; Pritchard, Robin Gavin; Bradshaw, Ian James; Hutcheon, Gillian Ann; Seton, Linda |
| Journal of publication | Acta Crystallographica Section C |
| Year of publication | 2011 |
| Journal volume | 67 |
| Journal issue | 12 |
| Pages of publication | o496 - o499 |
| a | 13.158 ± 0.002 Å |
| b | 15.63 ± 0.003 Å |
| c | 3.854 ± 0.001 Å |
| α | 90° |
| β | 90° |
| γ | 90° |
| Cell volume | 792.6 ± 0.3 Å3 |
| Cell temperature | 100 ± 2 K |
| Ambient diffraction temperature | 100 ± 2 K |
| Number of distinct elements | 4 |
| Space group number | 33 |
| Hermann-Mauguin space group symbol | P n a 21 |
| Hall space group symbol | P 2c -2n |
| Residual factor for all reflections | 0.1411 |
| Residual factor for significantly intense reflections | 0.0881 |
| Weighted residual factors for significantly intense reflections | 0.1726 |
| Weighted residual factors for all reflections included in the refinement | 0.2022 |
| Goodness-of-fit parameter for all reflections included in the refinement | 0.98 |
| Diffraction radiation wavelength | 0.71073 Å |
| Diffraction radiation type | MoKα |
| Has coordinates | Yes |
| Has disorder | No |
| Has Fobs | Yes |
| Revision | Date | Message | Files |
|---|---|---|---|
| 201957 (current) | 2017-10-13 | cif/2/ Marking COD entries in range 2/01 that are known to be related to ChemSpider entries using the _cod_related_entry data loop. |
2018308.cif 2018308.hkl |
| 180852 | 2016-04-02 | cif/2/01/ (antanas@echidna) Replacing _[local]_cod_* tags with their equivalents from the COD CIF dictionary in multiple entries in subrange 2/01/83. |
2018308.cif 2018308.hkl |
| 176760 | 2016-02-20 | cif/2/ (antanas@kurmis) Replacing _[local]_cod_* tags with their equivalents from the COD CIF dictionary in multiple entries in subrange 2/01. |
2018308.cif 2018308.hkl |
| 125873 | 2014-10-25 | cod/ (saulius@koala.ibt.lt) Adding DOIs to 1887 Acta Cryst. CIFs, their DOIs fetched using ACCE codes. |
2018308.cif 2018308.hkl |
| 88064 | 2013-08-29 | Adding _cod_database_fobs_code data item to all COD CIFs that have Fobs deposited and did not have this data item yet. | 2018308.cif 2018308.hkl |
| 31968 | 2012-01-03 | hkl/ Adding automatically assigned IUCr Fobs data for the rest of the year 2001 structures. |
2018308.cif 2018308.hkl |
| 31429 | 2012-01-02 | ../uploads/cif-deposit/cod/cif Adding structures of 2018307, 2018308 via cif-deposit CGI script. |
2018308.cif |
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Users of the data should acknowledge the original authors of the
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