Thymine hydrogen peroxide 0.55-solvate 0.45-hydrate

Thymine crystallizes from 50% hydrogen peroxide to give the title hydrogen peroxide water solvate, C5H6N2O2 center dot 0.55H(2)O(2)center dot 0.45H(2)O. The disordered peroxide and water molecules occupy the same positions. Thymine molecules are linked together by N-H center dot center dot center dot O hydrogen bonds forming chains parallel to the ac diagonal. Hydrogen peroxide molecules are combined by O-H center dot center dot center dot O hydrogen bonds to give chains parallel to the c axis. Both kinds of chains are organized in a three-dimensional hydrogen-bonded network.