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The microcapillary techniques and Taylor-Aris dispersion theory were used to determine the translational diffusion constant, D, of C60 in the even n-alkanes c-C(sub 6)H(sub 14) to n-C(sub 16)H(sub 34). The data can be utilized in D/T=A(sub se)/n(super p) with p = 0.903 plusmn 0.006 (p=1 for Se relation).

The translational diffusion constant, D, of dioxygen, O2, was measured by cycloalkanes using Taylor-Aris dispersion theory. The devalued were discussed in terms of computer simulations for small penetrants in hydrocarbons, the molar volumes of the solvents and free volume approaches.

A study was conducted to determine the translation diffusion constant of dioxygen in n-alkane solutions through a microcapillary by a minimized pressure. The passage of O2 through the capillary was observed using its ultraviolet absorption at 190 nm. The elution profiles utilized to calculate the diffusion constant were determined by using reduced pressure to draw oxygenated and deoxygenated n-alkanes. Results indicated that decreases in the diffusion constants correlated with increases in the chain length.

The low temperature (T) optical spectra of the isolated CP47 antenna complex from Photosystem II (PSII) with a low-T fluorescence emission maximum near 695 nm are reported. The 695 nm fluorescence maximum which shifts blue with increasing fluence provide important constraints and parameters for future excitonic calculations and offer new insight into the excitonic structure and composition of low-energy absorption traps.

The results of a series of Monte Carlo simulations are presented by using the 3.0-Angstrom structure of the photosystem II (PSII) core complex from cyanobacteria to model absorption, emission, persistent, and transient hole burned (HB) spectra. The excitonic calculations have shown that the best chlorophyll (Chl) candidates that contribute to the low-energy A and B states are Chl 44 and Chl 37.

The model of uncorrelated excitation energy transfer (EET) is applied to fit simultaneously absorption, emission, zero-phonon action and transient hole burned (HB) spectra obtained for the CP43 complex with minimized contribution from aggregation. The studies have shown that the persistent holes have originated from regular NPHB accompanied by the redistribution of oscillator strength due to excitonic interaction, rather than photoconversion involving Chl-protein hydrogen bonding.

The traslational diffusion constants, D, of biphenyl, diphenylacetylene, diphenylbutadiyne, anthracene, pyrene, rubrene, perylene, and coronene are determined in the n-alkanes using capillary flow techniques. The solutes show varying degrees of deviation from the Stokes-Einstein relation for D, however, it is seen that the values of hydrodynamic radius decreases as the viscosity increases.