X-ray studies near the Ad - A2 critical point in a binary system of successive homologues

Abstract

We have observed on the basis of X- ray studies a Ad-A2 critical point in a binary mixture of homologues belonging to the 4-n-alkyloxyphenyl 4'-( 4"-cyanobenzyloxy 1 - benzoate series (nOPCBOB). The critical point exists between the l0th and 11th member for a molar fraction of xc = 0.44 of the latter. Below Xc the layer spacing shows a distinct jump at the Ad-A2 transition whereas a smooth evolution is seen for X > Xc in the supercritical region.