X-ray powder patterns on anhydrous sodium palmitate show that the five phases already known to occur between crystal and isotropic melt can be grouped into two basic structures. Both structures are liquid crystalline, i.e., crystalline in the direction of the long spacing and liquid-like laterally. Between the lower temperature "waxy" structure, which includes the previously known subwaxy, waxy, and superwaxy phases, and the higher temperature "neat" structure, which includes subneat and neat, there is a pronounced break in the curve of long spacing vs. temperature; in addition, the three waxy phases exhibit two diffuse short spacing rings, whereas the neat phases exhibit only one. These pattern differences lead to the interpretation that the waxy phases contain structural restraints on molecular position and motion not present in the neat phases.

The Phase Nature of Beta Sodium Palmitate 141 method in rats proved to be identical. An explanation for this was found in the ability of the rat to convert neovitamin A to vitamin A.5. Catalytic interconversion of the anthra-quinone carboxylate esters of the two vitamins was accomplished in vitro by the action of iodine in benzene solution.

SOAP SYSTEMSAlthough the short spacings of x-ray diffraction patterns have proved most suitable for identification of at least four crystalline modifications of sodium soap, it is necessary to turn to the loiig spacings in order to ascertain the crystallization behavior of the individual fatty constituents of mixed and commercial soaps. The present study, based on long-spacing data, indicates that fractionation into the constituent