Structure of dibenzofuran-d8, C12D8O, at 173 K

Crystalline dibenzofuran-d8 has been found to exhibit disorder of the type described previously for dibenzofuran. The disordered molecules are related to the ordered molecules by a 180 degrees rotation about an axis passing through the molecular center of mass and perpendicular to the furan ring. In the present structure 11(2)% of the molecules were found to adopt this alternate orientation. The molecules are bisected by a mirror plane normal to the furan ring and containing the O atom. The average bond length in the benzenoid ring is 1.392 (10) A. The furan ring and the benzenoid ring are separately planar, but form a dihedral angle of 1.45 (9) degrees with each other.