  Synchrotron X-ray diffraction experiments and molecular dynamics simulations
have been performed on simple aliphatic aldehydes, from propanal to nonanal.
The performance of the OPLS all-atom interaction potential model for aldehydes
has been assessed via direct comparison of simulated and experimental total
scattering structure factors. In general, MD results reproduce the experimental
data at least semi-quantitatively. However, a slight mismatch can be observed
between the two datasets in terms of the position of the main diffraction
maxima. Partial radial distribution functions have also been calculated from
the simulation results. Clear differences could be detected between the various
O-H partial radial distribution functions, depending on whether the H atom is
attached to the carbon atom that is doubly bonded to the oxygen atom of the
aldehyde group or not.
