Orientational structure and dynamics of ethane confined in ZSM5 zeolite at four different loadings are reported. The effect of pore geometry on ethane is studied by isolating the contribution from ethane molecules in different locations, viz. straight channels, sinusoidal channels and their intersections. Orientational dynamics is found to be hindered in general and exhibits librational motion, with the extant of hindrance being the greatest in sinusoidal channels. Librational motion becomes faster with an increase in loading. This counterintuitive finding is consistent with experiments reported elsewhere and is explained on the basis of a decreased orientational anisotropy at higher loadings. (C) 2016 Elsevier B.V. All rights reserved.