摘要
Optimum resolution data of X-ray pow- der diffraction for 7-amino desacetoxy cephalospo- ranic acid(7-ADCA) were collected from an X′ Pert Pro MPD diffractometer with the setup of 0.01°/s and 0.01° per step. Indexing to the crystal system and searching space group from the diffraction data were conducted by means of the computational crystal- lography method. The pilot crystal models of 7-ADCA were then refined by Rietveld method to obtain the exact three-dimensional structure. The results show that the crystal structure of 7-ADCA is monoclinic, space group P21 with unit cell dimensions a=13.50 ?, b=6.01 ?, c =5.91 ?, α= γ =90.00°, β =101.96°, Z=2 and V =469.10 ?3. The fraction coordinate of each atom in the unit cell is well located and reported.
Optimum resolution data of X-ray powder diffraction for 7-amino desacetoxy cephalosporanic acid（7-ADCA） were collected from an X＇ Pert Pro MPD diffractometer with the setup of 0.01°/s and 0.01° per step. Indexing to the crystal system and searching space group from the diffraction data were conducted by means of the computational crystallography method. The pilot crystal models of 7-ADCA were then refined by Rietveld method to obtain the exact three-dimensional structure. The results show that the crystal structure of 7-ADCA is monoclinic, space group P21 with unit cell dimensions a=13.50 A^°, b=6.01 A^° c =5.91 A^°α= γ=90.00°,β=101.96°, z=2 and V=469.10 A^°3. The fraction coordinate of each atom in the unit cell is well located and reported.
