Crystal packing of a homologous series beta '-stable triacylglycerols

From a homologous series of CnCn+2Cn (n = even) triacylglycerols which are beta'-stable, Guinier X-ray powder diffraction photographs were used to det ermine cell parameters and space groups. The powder diffraction patterns ar e consistent with a pseudo-orthorhombic unit cell with space group Ic2a. On ly one axis is changing as a function of chain lengthening. The experimenta l results were used to propose a beta'-crystal packing for triacylglycerols . In contrast to earlier proposed beta'-crystal structures, the acyl chains of this structure are not tilted with respect to the methyl-end group plan e. Furthermore, with only one molecule in the asymmetric unit, overall orth ogonal chain packing is obtained when the intramolecular acyl zigzag planes are parallel.