Molecular Orbital Theory of the Hydrogen Bond. III. Dimers Containing NH2OH, H2O, HOF, and H2O

Ab initio calculations using a minimal STO‐3G basis set have been performed on the pairs of mixed dimers ${\mathrm{NH}}_2\mathrm{OH}–{\mathrm{H}}_2\mathrm{O}$ and $\mathrm{HOF}–{\mathrm{H}}_2\mathrm{O}$ , and on (NH₂OH)₂ and (HOF)₂. Equilibrium structures and energies are reported and analyzed for each. It is found that all dimers have equilibrium open chain structures except (NH₂OH)₂, which exists as a cyclic dimer. Two stable dimer structures of comparable energies are found for the mixed dimer $\mathrm{HOF}–{\mathrm{H}}_2\mathrm{O}$ which has HOF as the proton donor molecule, and for (HOF)₂. In the entire series of dimers $\mathrm{ROH}–{\mathrm{H}}_2\mathrm{O}$ and (ROH)₂, calculated dimer properties are analyzed as a function of the substituent R, and correlations are made where possible.