Effects of cetyltrimethylammonium bromide (CTABr) micelles on second-order rate constants (k(n)(obs)) for nucleophilic reactions of amines (piperidine and n-butylamine) with ionized phenyl salicylate (PS(-)) reveal a nonlinear decrease with the increase in [D(n)] (where [D(n)] = [CTABr](T) - cmc) at a constant [NaBr] and 35 degrees C. The observed data, at a constant [NaBr], fit reasonably well to a pseudophase model of micelles, and such a data fit gives kinetic parameters such as CTABr micellar binding canstant (K(S)) of PS(-). The effect of [NaBr] upon K(S) is explained with the empirical relationship K(S) = K(S)(0)/(1 + psi[NaBr]), where psi is an empirical parameter.

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The methanolysis of ionized phenyl salicylate, PS -, has been studied in the absence and presence of 0.03 M cetyltrimethylammonium bromide, CTABr, at 0.01 M NaOH and within the CH3OH content range of 10-80 or 90% (v/v). The pseudo-first-order rate constants, kobs, remain unchanged with change in [CTABr]T from 0.0 to 0.03 M at g65% (v/v) CH3OH. The ratio, kobs(0.0 M CTABr)/kobs(0.03 M CTABr) decreases from 4.6 to 1.1 with increase in CH3OH content from 10 to 60% (v/v). At the constant temperature and [CH3OH]T, the rate constants, kobs, show a decrease with increase in [CTABr]T. These results are explained in terms of a pseudophase model of micelle. At 30°C, the pseudo-first-order rate constants, k M MeOH , for the reaction of CH3OH with PS -in the micellar pseudophase and cmc of CTABr increase from 9.63 × 10 -4 and 1.8 × 10 -4 to 78.8 × 10 -4 s -1 and 60.0 × 10 -4 M, respectively, while the binding constants, K1, decrease from 8080 to 39 M -1 with increase in methanol content from 10 to 50% (v/v). Similar results are obtained at different temperatures ranging from 25 to 45°C. The activation parameters, ∆H* and ∆S*, for k M MeOH are larger than those for k NM MeOH (where k NM MeOH represents pseudo-first-order rate constant for the reaction of CH3OH with PS -in the nonmicellar pseudophase) at 10, 20, and 30% (v/v) CH3OH. These results are attributed to the increased ground-state stability of a monomeric methanol in the micellar pseudophase compared to that in the nonmicellar pseudophase. The thermodynamic parameters, ∆H0 and ∆S0, for binding constant, K1, reveal the decrease from -8.6 and -10.5 to -14.1 kcal/mol and -31.9 cal/(K mol), respectively, with increase in CH3OH content from 10 to 30% (v/v). Significantly lower values of k M MeOH compared to those of k NM MeOH at low contents of CH3OH are ascribed to (i) reduced [CH3OH] in the micellar pseudophase, where PS -molecules exist, compared to [CH3OH] in the nonmicellar pseudophase and (ii) partial loss of the efficiency of intramolecular general base catalysis due to probable ion-pair formation between anionic site of micellized PS -molecule and the cationic micellar headgroups.

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Greenockite (CdS) nanostructured thin films are deposited on soda and FTO conducting glass substrates by aerosol‐assisted (AA)CVD using a single‐source precursor bis‐(N,N‐dicylcohexyldithiocarbamato)(pyridine)cadmium(II), Cd[S2CNCy2]2.py (1), in pyridine, toluene, and THF solutions in the temperature range 350–450 °C. The precursor 1, characterized by physicochemical methods, undergoes facile thermal decomposition at 350 °C to give a stable residual mass of CdS. The thin films deposited from pyridine solution, and characterized by X‐ray diffraction (XRD), UV‐vis spectroscopy, field‐emission scanning electron microscopy (FESEM), and energy dispersive X‐ray (EDX) techniques, exhibit a band gap of 2.4 eV and a photocurrent density of 1.3 mA cm−2 at 0.4 V versus Ag/AgCl/3M KCl, suggesting their suitability for application in photoelectrochemical (PEC) cells.

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Effects of cetyltrimethylammonium bromide (CTABr) micelles on second-order rate constants (k n obs) for the nucleophilic reactions of amines (n-butylamine, piperidine, and pyrrolidine) with ionized phenyl salicylate (PS-) reveal a decrease of nearly 4-fold for n-butylamine, 13-fold for piperidine, and 17-fold for pyrrolidine with an increase in [CTABr]T from 0.0 to 0.01 M at 35 °C. These results show that the binding constants (K N) of amines with CTABr micelles vary in the order K N for n-butylamine > K N for piperidine > K N for pyrrolidine. The observed data are explained in terms of the pseudophase model of the micelle. The values of K N for n-butylamine, piperidine, and pyrrolidine turn out to be so small that they could not be determined kinetically. The significantly lower rate of aminolysis in the micellar pseudophase compared to that in the aqueous pseudophase is attributed to both micellar medium effect and different locations of amine and PS- in the micellar pseudophase.

Perovskite-structured lead titanate thin films have been grown on FTO-coated glass substrates from a single-source heterometallic molecular complex, [PbTi(μ2-O2CCF3)4(THF)3(μ3-O)]2 (1), which was isolated in quantitative yield from the reaction of tetraacetatolead(IV), tetrabutoxytitanium(IV), and trifluoroacetic acid from a tetrahydrofuran solution. Complex 1 has been characterized by physicochemical methods such as melting point, microanalysis, FTIR, (1)H and (19)F NMR, thermal analysis, and single-crystal X-ray diffraction (XRD) analysis. Thin films of lead titanate having spherical particles of various sizes have been grown from 1 by aerosol-assisted chemical vapor deposition at 550 °C. The thin films have been characterized by powder XRD, scanning electron microscopy, and energy-dispersive X-ray analysis. An optical band gap of 3.69 eV has been estimated by UV-visible spectrophotometry.