The Crystal Structure of a Photodimer of 1,4-Epoxy-1,4-dihydronaphthalene
The crystal structure of a photodimer of l,4-epoxy-1,4-dihydronaphthalene, with empirical formula C_(20)H_(16)O_2, has been determined by the application of direct methods. Three-dimensional data were collected on a Datex-automated General Electric diffractometer to a minimum spacing of 1·0 Å. The coordinates of all atoms in the molecule, the isotropic temperature factors for the hydrogen atoms, and the anisotropic temperature factors for the other atoms were refined by the method of least squares. The final R index was 0·027. The crystals are orthorhombic, space group Pcɑ2_1 with ɑ = 16-52, b = 7·975 and c= 10·58 Å. Of four possible configurations, the molecule of the photodimer has the exotrans-exo configuration. Despite the lack of a center of symmetry in the space group, the molecule is centrosymmetric almost within experimental error.
Additional Information© 1970 International Union of Crystallography. Received 2 September 1969. This work was aided by Grant No. GB-6617X from the National Science Foundation and Grant No. 12121-04 from the United States Public Health Service. We wish to express our thanks to Dr Richard E. Marsh for advice and guidance throughout this project. The preparation of drawings by Miss Lillian Casler and of the manuscript by Miss Allison Kimball is gratefully acknowledged.
Published - a07523.pdf