1987 Volume 35 Issue 4 Pages 1564-1570
The crystallite orientation in intact tablets was investigated by X-ray diffraction methods. XRay diffraction patterns were obtained by the symmetrical-reflection method and the symmetrical-transmission method. Crystallite orientation was evaluated by comparing the diffraction intensities obtained experimentally with those calculated theoretically from the structure factors for the respective planes of the crystal. The (100) planes of aspirin crystallites and the (110) and the (120); (210) planes of salicylic acid crystallites were found to align parallel to the upper surface of the tablet during compression. The crystallite orientation varied with applied pressure for salicylic acid tablet. The flat film technique (pinhole technique) was also used and the results obtained agreed well with those obtained by the diffractometric methods.
