Table 1. Crystallographic data of leucopterin hemihydrate and 0.2-hydrate.
| Hemihydrate | 0.2-Hydrate | |
|---|---|---|
| Structure from | Single-crystal data | Powder data/Rietveld refinement |
| Crystal data | ||
| Chemical formula | C6H5N5O3·0.5H2O | C6H5N5O3·∼0.2H2O a |
| CCDC reference | 2191333 | 2191321 |
| M r | 204.16 | 198.5 (33) b |
| Crystal system | monoclinic | monoclinic |
| Space group (No.) | P2/c (13) | P2/c (13) |
| Z, Z’ | 4, 1 | 4, 1 |
| Temperature (K) | 296 (2) | 296 (2) |
| a (Å) | 8.0781 (10) | 8.1026 (4) |
| b (Å) | 4.7930 (6) | 4.8366 (3) |
| c (Å) | 18.345 (2) | 17.8289 (14) |
| α (°) | 90. | 90. |
| β (°) | 90.223 (8) | 88.531 (4) |
| γ (°) | 90. | 90. |
| V (Å3) | 710.28 (15) | 698.46 (8) |
| ρcalc (kg dm−3) | 1.9091 (4) | 1.888 (32) b |
| Radiation type | Cu Kα | Cu Kα1 |
| Wavelength (Å) | 1.54178 | 1.5406 |
| μ (mm−1) | 1.392 | 1.365 |
| Data collection | ||
| Crystal size (mm) | 0.03 × 0.03 × 0.002 | powder |
| Diffractometer | Siemens/Bruker three-circle | Stoe Stadi-P |
| Specimen mounting | glass pin | 0.7 mm capillary |
| Data collection mode | CCD detector | step |
| Detector | APEXII CCD | linear PSD |
| 2θmin (°) | – | 4 |
| 2θmax (°) | – | 70 |
| 2θstep (°) | – | 0.2 |
| Refinement | ||
| R1 | 14.6% | – |
| wR2 | 44.5% | – |
| R p (%) | – | 2.516 |
| R wp (%) | – | 3.454 |
| R exp (%) | – | 2.171 |
| R p′ (%) c | – | 10.091 |
| R wp′ (%) c | – | 10.517 |
| R exp′ (%) c | – | 6.609 |
| GOF | 2.41 | 1.591 |
| No. of data points | – | 7800 |
| No. of reflections in refinement | 309 | 310 |
| No. of refined parameters | 57 | 101 |
| No. of restraints | 2 | 52 |
| H-atom treatment | calculated | refined with restraints |
Notes: (a) The water content is uncertain; it could also be 0.1 or 0. (b) The high uncertainties of these values are caused by the uncertain amount of water in the structure. (c) The R p′, R wp′ and R exp′ values are background-corrected data according to Coelho (2004 ▸).