X-ray diffraction study of liquid n-butane at 140 and 267 K

Abstract

X-ray diffraction data for liquid n-butane near the triple and boiling points are presented. The data are analyzed using scattering factors for −CH3 and −CH2 groups which permits extraction of structure and distribution functions for carbon sites. An intramolecular carbon–carbon distance at approximately 3.1 Å is assigned to a short end-to-end distance in a near-gauche conformation, which is in agreement with the electron diffraction results for gaseous n-butane. The intermolecular pair distribution functions show a large difference in the liquid structure for the low and high temperature states, similar to that found in liquid propane.