Thermal neutron diffraction from the liquids N2 and O2. Determination of nearest neighbor parameters and angular correlations

Abstract

Using a double axis crystal spectrometer, we have determined the structure factor S (κ) of the liquids N2 and O2 up to a maximum wavevector κm=11 Å−1. We derive the parameters characterizing the first nearest neighbor shell and find that the intramolecular bond length is well determined, whereas the width and the volume of the shell is derived with rather large uncertainties. We also demonstrate how our data analysis program may be used to give necessary limits for κm, dependent upon which parameters are to be determined. Finally, we deduce the angular correlations which give a result consistent with the dominant quadrupolar and dipolar interactions in N2 and O2, respectively.