An 'intrinsic' value of the adsorption Gibbs energy (DELTA-G(int)-degrees) parallel-to, not directly proportional to the measured DELTA-G(ads) parallel-to, has been evaluated for a set of 28 aromatic, heterocyclic and naphthalenic derivatives. The structural feature of (DELTA-G(int)-degrees) parallel-to is rationalised in terms of a 'soft' interaction with mercury at the point of zero change, on the basis of the Parr and Pearson concept, accounting on a quantitative basis for the different adsorbability of the compounds. Moreover, the partial charge-transfer coefficient, lambda, has been related in a satisfactory way to DELTA-N (the fractional number of electrons transferred) calculated taking into account the absolute electronegativity, chi, and the hardness, eta, both of the adsorbate and of mercury.
ELECTROSORPTION OF HARD AND SOFT AROMATIC DERIVATIVES ON MERCURY / Benedetti, L; Gavioli, Gb; Fontanesi, Claudio. - In: JOURNAL OF THE CHEMICAL SOCIETY. FARADAY TRANSACTIONS. - ISSN 0956-5000. - 88:(1992), pp. 843-847.