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A facile method for photochemically preparing high molecular weight polyfullerenes has been developed. The method involves subjecting polyfullerenes to a room-temperature solution under oxygen-free conditions. The polyfullerenes and the clusters from which polymers were prepared exhibited comparable sizes. The potential use of polyfullerenes in molecular conduction, nonlinear optics and hydrogen storage was examined.

The fluorescence quenching of polyaromatic molecules by carbon tetrabromide (CBr4) is studied. Specifically, the fluorescence lifetimes of 9,10-bis(phenylethynyl)anthracene (BPEA) in supercritical carbon dioxide (CO2) was estimated as a function of CBr4 densities via time-correlated, single-photon counting. The results confirmed the enhancement of bimolecular reactions leading to fluorescence quenching in supercritical CO2 at near-critical densities. The results suggest a solute-solute clustering mechanism from higher local quencher concentration.

A chemometrics spectral method helps determine pure absorption and fluorescence spectra of ground state charge transfer complexes and exciplexes of C60 and C70 with N, N-diethylaniline (DEA) and N,N-dimethylaniline (DMA). Solvents exhibit strong influence on exciplex emission, and both dynamic and static process participate in the quenching of monomer fluorescence. A mechanism of prompt and delayed monomer emissions explains the observation of dual fluorescence for C60/C70-DEA/DMA in hexane.

Analyses performed in near-critical liquid ethane, CO2 and their mixtures with hexane, established at room temperature, fluorescence spectra and quantum yields for tetraphenylethylene (TPE). The delayed fluorescence spectrum of TPE is obtained. The twisted excited state is zwitterionic in nature.

The characteristics of the twisted excited state of tetraphenylethylene in supercitical fluids are studied. Picosecond transient absorption measurements are performed on unpurified tetraphenylethylene with an Nd:YAG laser acting as the excitation source. Tetrahydrofuran amd n-hexane are used as received. Results reveal that the twisted excited state lifetime of tetraphenylethylene in supercritical fluid-cosolvent mixtures is very sensitive to changes of medium properties.

The photophysical properties of permethylhexasilane (Si6Me14) was determined using ultraviolet spectroscopy and Si6Me14 was found to be different from other longer oligosilanes. However, its fluorescence is not what is expected from an extrapolation from longer chains. It is proposed that the lowest singlet state nature changes between Si10Me22 and Si6Me14. It also favors one of the three possible tentative assignments for the emitting state of Si6Me14. Moreover, thetemperature-dependence of the Si6Me14 fluorescence quantum yield suggests the existence of a thermally activated radiationless decay channel.

Fluorescence measurements were conducted on all-trans-1,6-diphenyl-1,3,5-hexatriene in methylcyclohexane. Resolution of the compound's spectra featured a mixture of 2(super 1) A(sub g)/1(super 1) B(sub u) and red-shifted fluorescence spectra from all-s-trans and s-cis conformers, respectively. Principal-component analysis with self-modeling calculations confirmed the temperature dependence of the compound's s-cis conformers.

The solute-solvent interactions of p-(N,N-dimethylamino)benzonitrile and ethyl p-(N,N-dimethylamino)benzoate in supercritical trifluomethane, carbon dioxide and ethane solutions were examined using absorption and emission spectral measurements. The results indicated that varying densities affected the spectral shifts exhibited by the two compounds. The spectral shifts were were further categorized in three intermolecular interactions characterized as gaslike, near-critical and liquidlike densities.

The derivative porphyrin tetrakis-21H, 23H-prophine (THPP) selectively interacts with and solubilizes semiconducting single-walled porphyrin tetrakis(SWNT), resulting in the 'extraction' of most of the semiconducting SWNTs from the starting purified nanotube sample.

Reports on quantitative studies of ground and excited state charge transfer complexes of fullerenes with N,N-dimethylaniline and N,N-diethylaniline. Determination of pure absorption spectra of ground state complexes and pure exciplex fluorescence spectra; Fluorescence quenching in hexane.

Rational design and regulation of atomically precise photocatalysts are essential for constructing efficient photocatalytic systems tunable at both the atomic and molecular levels. Herein, we propose a platform-based strategy capable of integrating both pore space partition (PSP) and open-metal sites (OMSs) as foundational features for constructing high-performance photocatalysts. We demonstrate the first structural prototype obtained from this strategy: pore-partitioned NiTCPE- pstp (TCPE = 1,1,2,2-tetra(4-carboxylphenyl)ethylene, pstp = partitioned stp topology). Nonpartitioned NiTCPE- stp is constructed from six-connected [Ni 3 (μ 3 -OH)(COO) 6 ] trimer and TCPE linker to form 1D hexagonal channels with six coplanar OMSs directed at channel centers. After introducing triangular pore-partitioning ligands, half of the OMSs were retained, while the other half were used for PSP, leading to unprecedented microenvironment regulation of the pore structure. The resulting material integrates multiple advanced properties, including robustness, wider absorption range, enhanced electronic conductivity, and high CO 2 adsorption, all of which are highly desirable for photocatalytic applications. Remarkably, NiTCPE- pstp exhibits excellent CO 2 photoreduction activity with a high CO generation rate of 3353.6 μmol g -1 h -1 and nearly 100% selectivity. Theoretical and experimental studies show that the introduction of partitioning ligands not only optimizes the electronic structure to promote the separation and transfer of photogenerated carriers but also reduces the energy barrier for the formation of *COOH intermediates while promoting CO 2 activation and CO desorption. This work is believed to be the first example to integrate PSP strategies and OMSs within metal-organic framework (MOF) photocatalysts, which provides new insight as well as new structural prototype for the design and performance optimization of MOF-based photocatalysts.