DR plots are given for three carbons of series M with increasing degree of oxidation. These results may be summarized as follows:(i) The polarity of the adsorptive prevents the filling of the micropores at low relative pressures as noted by the decrease in slope ratios from N2 to HzO.(ii) The polar moment is not the only factor to explain the deviations (relative to N2) found for SO2, CH30H, and H20 (they have very similar values); neither is the hydrogen bond by itself because is similar for water and methanol. The most important factor seem to be a low nonspecific adsorbatecarbon interaction and a high adsorptive-adsorptive interaction.(iii) The differences between C H 3 0 H and SO2 suggest that hydrogen bond causes a larger deviation than the simple polar moment interaction.(iv) Increasing degree of oxidation increases the carbon-adsorbate interaction, the adsorption mechanism approaching then that of N2, micropore filling with the adsorbate as liquid. Acknowledgment. This work was supported by CICYTThe effect of substituted ferrocene complexes on the surface of quantum-confined (Q) cadmium sulfide clusters in inverse micelles was examined by steady-state and time-resolved photoluminescence (PL) spectroscopy. Addition of (dimethylamin0)methylferrocene (DMAMF) to Q-CdS enhanced cluster PL peak areas by 120%, in contrast to the carboxylic acid derivatives ferrocenecarboxylic acid (FCA) and ferrocenedicarboxylic acid (FDCA), which quenched PL by 60% and 80%, respectively. Unsubstituted ferrocene, hydroxymethylferrocene, and ferrocenecarboxaldehyde had no effect on the PL intensity of these clusters. The induced PL changes fit a Langmuir-type adsorption isotherm from which formation constants for the Q-CdSsurface adducts were calculated. The average log Kf value calculated for DMAMF adsorption was 4.12. FCA addition gave an average log Kf of 5.17, and the average log Kf value for FDCA addition was 6.14. Binding of the amino group of DMAMF to shal!ow trap states arising from Cd2+ sites is postulated as its mechanism for PL enhancement, while the quenching mechanism for FCA and FDCA is attributed to proton transfer induced from ionization of the acids in the micelle water pools. "Competition" experiments show that quenching by the carboxylic acid derivatives can be reversed by the addition of amino-substituted ferrocene, and vice versa. The results also suggest a possible DMAMF-induced surface reconstruction. These steady-state observations are supported by measurements of the PL decay via subnanosecond timecorrelated single photon counting. Fits of the decay monitored at 620 nm to a modified stretched exponential model indicate that the average distributed decay time ( T 2 ) of nanosecond duration can be either lengthened or shortened, depending on the nature of the added ferrocene.

In this account the influence of charge possessed by the stabilizing medium on the steady-state quenching behavior of quantum confined cadmium sulfide (Q-CdS) semiconductor clusters is reported. Q-cluster stabilizers such as the inverse micelle/hexametaphosphate (HMP) system and thiophenol caps, which afford an anionic solution/stabilizer interface, permit quenching of the integrated trap photoluminescence (PL) intensity (Amx between 550 and 650 nm) up to -45% (HMP) or 54% (thiophenol) by the cation methyl viologen ( M V ) . However, minimal quenching is observed upon addition of the anion iodide (I-), and virtually no quenching is observed following the addition of neutral molecules (amines and ketones). This is in stark contrast to Q-CdS clusters stabilized by macrocyclic aminocalixarene stabilizer molecules, which give rise to a cationic layer (-NR2H+) at the solution/stabilizer interface. Integrated PL from aminocalixarene stabilized Q-CdS clusters can be quenched up to -70% by the addition of I-; however, negligible quenching is observed upon the addition amines, MV2+, or ketones. These differences in Q-cluster photoluminescence behavior are discussed in terms of possible electrostatic interactions of the various quenchers with the cationic/anionic Q-CdS charge layers.

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Integral sorption/desorption measurements were carried out for the sulfur dioxide‐glassy polyarylate polymer system at 25°C, 40°C, 55°C, and 63°C. The transport of sulfur dioxide in the glassy polyarylate polymer was governed by Fickian diffusion. The effective diffusion coefficient of sulfur dioxide increased with increasing penetrant concentration. The concentration dependence of the effective diffusion coefficient is explained on the basis of the partial‐immobilization model developed by Paul and Koros. The mobility of the molecules sorbed in the Langmuir mode is shown to be significantly lower than the mobility of the molecules in Henry's law dissolution mode. The predictions of permeability values as a function of upstream gas pressure are presented. The equilibrium sorption isotherms for this system are well represented by the dualmode sorption model. The eltergetics and the temperature dependence of the dual‐mode parameters are also discussed.

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