Methyl phosphate, bond angle

For hydrogen bonded complexes, one of the phosphate or sulfate oxygens not bonded to either a methyl group or hydrogen atom was considered the electron donor and a hydrogen atom of the substituent compound the electron acceptor, i.e., a linear 0 — -H -R bond was created. The 0-H and 0-R distances were varied and rotations of the R group about the H-bond axis made in 30° intervals for each 0-R distance. At the optimum values of the heavy atom distance and torsion angle,... 

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