No abstract

Indole crystallizes in the orthorhombic space group Pna2t with unit-cell parameters a= 7.86, b= 5"66, c= 14.89 A with four molecules per unit cell. The crystal structure was found to be disordered with the indole molecule capable of assuming two alternative orientations. The gross structure (R 0.23) was confidently predicted from the crystalline properties, weighted reciprocal lattice plot and by analogy with the structures of carbazole and the 1 : 1 complex of indole with s-trinitrobenzene, although it could not be carried to its logical stage of refinement because of very high interactions between the overlapping atoms.

2-hydroxy, 4-amine, w -w', dichloroacetophenone crystalizes in the monoclinic space group P2\\a with unit cell parameters a = 7.458(2), b = 9.109(1), c = 13.3997(26) Äand β = 99°.86(2), Cell vol. = 896.905 Ä 3 , d c = 1.63 g/ml, d a = 1.65 g/ml, μ(ΜοΑΓα) = 6.86 cm" 1 , F 000 = 480 and with four molecules per unit cell. The gross structure was confidently predicted in applying 'Patterson synthesis' method, which yielded R = 0.044 and S = 1.28, S, being the standard deviation of an observation with unit weight.

The C5-C11 distance of 3.77 /k between molecules II and III and the C3-C3 distance of 3.55 /~ between molecules I and II agree well with the distances of closest approach, 3.65 and 3.7 A respectively. In fact, a CH-CH distance between different molecules as low as 3.4 A has been recorded by Iball (1934) in chrysene. From the a c projection the angle C12-I-C 1 appears to be 86°(±1 ° ) and not 90 ° . The latter angle would have given a Cs-C11 distance of 3-51 J~, which is rather short.The packing of the molecules accounts for the existence of the cleavage plane parallel to (001).

Crystal structure / OxoethanophenanthreneAbstract. The crystal structure of oxoethanophenanthrene (C 17 H, 8 0) has been determined from three-dimensional X-ray diffraction data collected by Nonius CAD 4 diffractometer with MoATa-radiation. The compound crystallizes in the monoclinic space group Pljc with unit-cell parameters a = 10.109(4), b = 11.723(5), c = 11.159(10) Α, β = 94.24°(5), cellvolume = 1318.91 Aj,