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Self-assembled organic thin films of dodecanethiol (DT), mercaptobenzothiazole (MBT), benzotriazole (BTA), imidazole (IMD) and benzothiazole (BT) are formed by adsorption on the surface of copper thin film used in ultralarge-scale integrated circuits. The films are characterized by x-ray photoelectron spectroscopy. The inhibition of corrosion of these organic thin films is investigated in aerated 0.5 M H2SO4 solutions by electrochemical impedance spectroscopy and potentiodynamic polarization techniques. The presence of these films reduced corrosion by blocking the copper surface from the oxygen dissolved in the acid medium. The relative inhibition efficiencies of these inhibiting agents in preventing copper oxidation are found to be in the order of DT>MBT>BT>BTA>IMD. The effectiveness of the inhibitors increased with the temperature, concentration of the inhibitors, and duration of immersion in the solution. An adsorption model is proposed on the basis of variation of the impedance according to the inhibitor concentration. The stability and packing of the inhibitors on the surface appear to be the most important factors in determining the inhibitive efficiency of the inhibitors.

The reaction between bis(M-chloro)bis[(i?)-l-[(dimethylamino)ethyl]naphthylenyl-C2,lV]dipalladium(II) and 2 mol of the bidentate Ph2PCH2CH2SMe gave a pair of internal diastereomeric complex cations arising from the coordinated sulfur stereocenter. The hexafluorophosphate salt of the diastereomeric mixture crystallizes as a compound with [a]D -35°( CH2C12) in the triclinic space group PI with a = 7.8690 (10) A, b = 17.837 (2) A, c = 21.830 (2) A, a = 82.86 (1)°, ß = 87.19 (1)°, y = 83.39 (1)°, and Z = 4 (R = 0.0412 and Rw = 0.0666). In solution, the complexes exhibit facile intramolecular asymmetric equilibration between diastereomers epimeric at sulfur at room temperature. A coalescence temperature of -90 °C was recorded for the interconversion by variable-temperature NMR spectroscopy. Similar behavior was observed for analogous complexes of Ph2AsCH2CH2SMe and