Quantum-chemical interpretation of the reorientation of dialkyl-cis-9,10-dihydroanthracene-9,10-endofumarates on a silver-containing stationary phase

The chromatographic behavior of a series of dialkyl-cis-9,10-dihydroanthracene-9,10-endofumarates on a silver-containing stationary phase with various mobile phase compositions and at various temperatures was investigated by liquid chromatography. The observed relationships indicate reorientation of the analytes on the surface of the adsorbent with increase in temperature. This is explained by the formation of two types of chelate complexes similar in energy between the analytes and the silver ions. It agrees well with data calculated by the B3LYP/LANL2DZ method.