The crystal structure of phenoxatellurine dinitrate,C12H8O7N2Te

The crystal structure of phenoxatellurine dinitrate, C₁₂H₈O₇N₂Te, has been determined by x-ray diffractometer methods. The crystals are monoclinic, C2/c, a = 12.916(3), b = 14.050(5), c = 7.532(2) Å; β = 96.65(3)° at t = 22°. The molecule is nearly planar (175°), with the Te and O atoms of the central ring in special positions on the twofold symmetry axis. The bond distances for the central ring are: Te-C = 2.068(4) Å, C-O = 1.366(5), C-C = 1.388(6) with C-Te-C = 93.5(2)° and C-O-C = 128.2(5). The bond distances and angles in the phenyl rings do not differ significantly from the normally accepted values of 1.40 Å and 120°. The two nitrate groups are close to Te and are related by the twofold axis of symmetry. The independent distances and angles are: Te-O1 = 2.201(3), O1-N = 1.325(5), N-02 = 1.229(6), N-O3 = 1.204(6) Å, O2-N-O3 = 126.3(4), O1-N-02 = 117.1(4), O1-N-03 = 116.6(4)°. All hydrogen atoms were located at or near their calculated positions. The final R value for 1679 independent reflections was 0.031. The planarity of the molecule is discussed qualitatively in terms of simple molecular orbital theory.