The resonance energies for electron attachment to the chloromethanes are evaluated by means of bound and continuum multiple scattering Xα calculations. The results closely reproduce the experimental electron transmission spectroscopy data and confirm their previous assignment. Electron transmission and dissociative attachment spectra of monochloroalkanes are also reported, in order to obtain information on the effects of branching at the substituted carbon atom and of alkyl chain length on the resonance and chlorine anion production energies.

The electron transmission spectra of the fluoro~, bromo~, and iodomethanes (except CH 2 F 2 ) and of some monohaloalkanes are reported. The resonance energies for electron attachment to the halomethanes have also been evaluated by means of bound and continuum multiple scattering Xa calculations, which closely reproduce the low~energy experimental data. A large electron affinity increase is observed on going from the fluorine to the heavier halogen derivatives, while within each series of halides the electron affinity increases with increasing number of halogen atoms. The ground anion state is found to be stable in CHBr 3 , CBr 4 , and in all the iodomethanes except CH31. The fragment anion production, as a function of the electron impact energy, has been measured for some of the compounds under investigation, in order to obtain experimental information on anion states very close to zero energy or slightly stable, which are not accessible in electron transmission.

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The interaction of enantiomeric ketoprofen (KP) with BSA and HSA was studied by isothermal titration calorimetry (ITC). Affinity constants and thermodynamic parameters for complexation in two main protein sites were determined. Affinity constants for both proteins are generally lower for S(+)- than for R(-)-KP. Large enthalpic contributions to Gibbs free energy are compensated by large negative entropic terms for S(+) in the BSA-subdomain IIIA and HSA-subdomain IIA. The lowest energy BSA complexes of both enantiomers were structurally characterized by combining molecular mechanics (MM) and molecular dynamics (MD) with circular dichroism (CD). Comparison of quantum mechanically calculated rotational strengths with the CD signals of the complexes supported the structures. These allowed to identify the main interactions of the KP enantiomers with surrounding amino acids at short distances, that limit significantly KP mobility in both sites. In the primary binding site S(+) is close to Tyr 409 in subdomain IIIA (Sudlow site II), and R(-) is close to Trp 212 and His 240 in subdomain IIA (Sudlow site I). The same sites are involved in the formation of 2:1 complexes. The equilibrium structures are characterized by marked geometrical distortion of KP.

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