C60 In Toluene Research Articles

Photoacoustic signal saturation and optical limiting in C<sub>70</sub>-toluene solution

Pulsed photoacoustic studies in solutions of C70 in toluene are made using the 532-nm radiation from a frequency-doubled Nd:YAG laser. It is found that contrary to expectation, there is no photoacoustic (PA) signal enhancement in the power-limiting range of laser fluences. Instead, the PA signal tends to saturate during optical power-limiting phenomenon. This could be due to the enhanced optical absorption from the photoexcited state and hence the depletion of the ground-state popu- lation. PA measurements also ruled out the possibility of multiphoton absorption in the C70 solution. We demonstrate that the nonlinear ab- sorption leading to optical limiting is mainly due to reverse saturable absorption. © 1997 Society of Photo-Optical Instrumentation Engineers.

Solubility of Fullerene C60 and C70 in Toluene, o-Xylene and Carbon Disulfide at Various Temperatures

The solubilities of fullerene C60 and C70 in toluene, o-xylene and carbon disulfide between the melting point and boiling point of the solvents, respectively, have been measured. The temperature dependent solubility of C60 displays anomalous behaviors. A solubility maximum of C60 around 0 °C for toluene and carbon sulfide and around 30 °C for o-xylene was observed. The temperature-dependent solubility of C70 behaves normally for all the three solvents studied.

Elastic Polymer Guest-Host Optical Limiters

AbstractThis paper presents the results of the bulk laser damage performance of undoped epoxy thermosets with glassy and rubbery mechanical properties and two commercial polymethylmethacrylate (PMMA) samples. We demonstrate how thermomechanical properties such as glass transition temperature (Tg) and equilibrium shear modulus (Ge) affect laser damage threshold. The rubbery epoxy elastomer shows a damage threshold fluence one order of magnitude higher than PMMA and 2.5 orders of magnitude higher than a glassy epoxy thermoset. A solid-state guest-host limiter is made by doping the epoxy elastomer with zinc octabromotetraphenylporphyrin (ZnOBP). The limiting performance of the elastomer limiter is compared to a solution of ZnOBP and C60 in toluene. Photochemical hysteresis effects in the solid limiter were also investigated.

Synthesis of C60-Furfural Adduct

Abstract Diels-Alder cycloaddition of furfural to C60 in toluene has been realised. UV-VIS, FTIR and 1H-NMR investigations suggest that the conjugated structure of furfural was changed into a non-conjugated structure in the product.

Some Enthalpies of Solution of C60 and C70. Thermodynamics of the Temperature Dependence of Fullerene Solubility

The enthalpy of solution of C60 in toluene, carbon disulfide, decalin, and N,N-diethylaniline and of C70 in CS2 has been measured using an isoperibol solution calorimeter. Exothermic heats of solution are observed in all cases. The heat of solution of C60 in toluene is −8.6 ± 0.7 kJ mol-1; in carbon disulfide it is −20 ± 1 kJ mol-1. In decalin, slow dissolution prevents an accurate determination, but the heat of solution is less than −5 kJ mol-1. In N,N-diethylaniline, a fast exothermic step comparable to that observed in other systems is followed by a much larger heat evolution, implying that a chemical reaction is occurring. The heat of solution of C70 in CS2 is −9 ± 1 kJ mol-1. A thermodynamic theory of the temperature dependence of fullerene solubility is presented. The central idea is that the unusual temperature dependence of the solubilities of fullerenes is caused by the formation of solvated crystals. Conditions are derived under which a temperature maximum of solubility, caused by an incongruent...

Intensity scan and two photon absorption and nonlinear refraction of C60 in toluene

A single beam technique is introduced to determine the magnitude and sign of third order nonlinear optical coefficients of materials using intensity dependence of the complex refractive index. It is applicable to a large range of materials including those with a low damage threshold such as polymers and absorbing glasses. It is used to determine the two photon absorption and nonlinear refraction coefficients of C60 in toluene. Concentration dependence of the nonlinear optical coefficients results in second hyperpolarizabilities of 10−31 (esu) for C60.

Small-Angle X-ray Scattering and Mass Spectrometry Studies of γ-Irradiated C60 in Cyclohexane

Intense (1.42 krad/min) γ-radiolysis of C60 dissolved in cyclohexane (weak magenta-colored solution) to a total dose of 51 krad resulted in the formation of a new compound (muddy red in color) with a solubility of more than 30 times that of saturated C60 in toluene. Low-power, laser desorption Fourier transform mass spectrometry (LD-FTMS) of the product yielded two ions at m/z = 1539 and 1556, which correspond to [C60(cyclohexane)10−xH]+ for x = 23 and 6, respectively. Higher power laser desorption conditions as well as collision-induced dissociation experiments of selected ions show the sequential loss of cyclohexene (C6H10) units. Small-angle X-ray scattering (SAXS) of the dissolved material supports the mass spectrometry results of cyclohexane additions to the sphere. Taken together, the mass spectrometry and SAXS data indicate that the identity of the γ-radiolysis products of C60 in cyclohexane most likely are cyclohexyl adducts of C60, primarily C60(cyclohexane)10. The SAXS data further indicate that...

Extended projection of C60spheres into three-dimensional space-three–fold cycloaddition of [60]fullerene to hericene

Heating 2,3,5,6,7,8-hexamethylidenebicyclo[2.2.2]octane with an excess of C60 in toluene for 3–4 d gives the 1 : 3 multiple Diels–Alder adduct in low (ca. 10%) yield.

Cyclotriveratrylene polarisation assisted aggregation of C60

Excess cyclotriveratrylene (CTV) and C60 in toluene results in micelle-like aggregation of the fullerenes arising from CTV polarisation of the fullerene, leading to a one-dimensional zigzag polymeric array of fullerenes in the solid state, each in the cavity of a CTV molecule.

EPR studies of the excited triplet states of C60O and C60C2H4N(CH3) fullerene derivatives and C70 in toluene and polymethylmethacrylate glasses and as films

Abstract The EPR spectra of excited triplet states of two fullerene derivatives, C60O and C60C2H4N(CH3), in the glassy matrices of toluene and of polymethylmethacrylate (PMMA) and as films were examined at low temperature and the magnetic parameters were measured. In films, species with zfs parameters smaller than those in toluene were found and they were assigned to triplet excitations visiting more than one molecule in the crystallites that form the film. When C60C2H4N(CH3) was excited in PMMA grown by in sity thermal polymerization a new triplet species was originated characterized by a dipolar splitting constant D about three times larger than that measured in toluene. Evidence was gained that such species participates to cross-linking in the polymer. The effect of PMMA matrix on the molecular dynamics of 3C70 was also investigated. It was found that a dynamical model holds based on the pseudorotation of the molecule around the axis of larger dipolar splitting. Motion is activated with activation energy of 210 ± 50 cm−1 a value comparable with that obtained for pseudorotation of 3C70 in cyclohexane.

Comparative Study on Photoinduced Electron Transfer from N,N-Dimethylaniline (DMA) and 4,4'-Methylenebis(N,N-dimethylaniline) (BDMA) to C60 and C70 in Toluene

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTComparative Study on Photoinduced Electron Transfer from N,N-Dimethylaniline (DMA) and 4,4'-Methylenebis(N,N-dimethylaniline) (BDMA) to C60 and C70 in TolueneJeunghee Park, Dongho Kim, Yung Doug Suh, and Seong Keun KimCite this: J. Phys. Chem. 1994, 98, 48, 12715–12719Publication Date (Print):December 1, 1994Publication History Published online1 May 2002Published inissue 1 December 1994https://doi.org/10.1021/j100099a040RIGHTS & PERMISSIONSArticle Views214Altmetric-Citations32LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InReddit PDF (663 KB) Supporting Info (1)»Supporting Information Supporting Information Get e-Alerts

Light-induced absorption enhancement in C 60 toluene solution

Absorption enhancement induced by a pump beam of 532 nm in C60 toluene solution has been observed and studied from 560 nm to 630 nm, and the absorption cross section of its lowest triplet state has been determined in this wavelength range according to our theoretical model.

Self-mode-locking suppression with intracavity fullerenes

We present the experimental results on how to suppress self-mode-locking in a free-run or Q-switched Nd:YAG laser with intracavity fullerenes. It was demonstrated that the self-mode-locking was partly or completely suppressed when a certain sample containing fullerenes, such as C60 toluene solution, C60 in polystyrene host, or optical glass doped with fullerenes, was placed within the laser resonator, and that the degree of suppression was dependent upon the length and fullerenes concentration of the sample. Qualitative analysis showed that the nonlinear absorption of the intracavity fullerenes resulted in this effect.

Polyether-modified fullerenes

Polyether-modified fullerenes have been prepared under mild conditions by reacting C60 or C70 in toluene with a precursor poly(oxyethylene) or poly(oxypropylene) polymer possessing amino end-groups. In the early stages of the interaction, soluble products are formed. Later, cross-linking proceeds between the polyfunctional fullerenes and the bifunctional polyethers. The non-crosslinked fullerene derivatives are soluble both in toluene and water; by evaporation of toluene, very adhesive films are formed.

Anomalous optical response of C60 and C70 in toluene.

Anomalous optical response of C60 and C70 in toluene.

Diffusion of C60 in porous sol-gel glass

Molecular dynamics computer simulation and experimental data for diffusion of cyclohexane and toluene solutions of C60 inside porous sol-gel glass are reported. The average pore diameter of the glass used in the experiment was 2.8 nm, similar to that used in computer simulations, 2.5 nm. Translational motion of C60 in solutions in the pores is about 10 times slower than the diffusion in the carrier. It is shown that thermally stable sol-gel glass samples can be uniformly impregnated with C60 by diffusing C60 toluene solutions into the pores. Optical spectra of wet and dry impregnated samples are similar.

Theoretical and Experimental Investigations of Fullerene Derivatives: C60H2, C60H4, C70H2, AND C60(CH2)2

ABSTRACTHydroboration of C70 in toluene yields a 2:1 mixture of 1,9-C70H2 and 7,8-C70H2. Equilibration of these two isomers in the presence of a Pt catalyst reveals a free energy difference of 1.4 ± 0.2 kcal/mol. Whereas semiempirical calculations have been found to predict the energy ordering of many fullerene derivatives incorrectly, ab initio Hartree-Fock (HF) calculations have been found to yield quantitative predictions of experiment. The HF/6-31G* level energy separation of l,9-C70H2 and 7,8-C70H2 of 1.3 kcal/mol is in excellent agreement with experiment. Relative stabilities of isomers of bis(methano)fullerenes were found to parallel those of analogous C60H4 isomers. Density functional theory (DFT) methods have been tested and are equivalent in accuracy to HF methods if similar basis sets are used. C60H2 and C60H4 can be efficiently produced on larger (≥ 50 mg) scales with diimide generated from potassium azodicarboxylate and acetic acid in o-dichlorobenzene.

STUDIES ON THE CHARACTERISTICS OF ALL-OPTICAL SWITCHING BASED ON THE EXCITED STATE ABSORPTION OF C60 MOLECULES

We have obtained the characteristics of all-optical switching and modulation of C60 in toluene pumped by a pulsed Nd:YAG laser at λ=532.0nm and probed by a CW semiconductor laser at λ=747.0nm, based on nonlinear triplet-triplet absorption in C60. Dynamic processes of switching and modulation are simulated using rate equations, which coincide with the experimental results.

Nonlinear absorption study of a C_60–toluene solution

Nonlinear absorption at 532 nm in a C60–toluene solution by using 8-ns and 30-ps laser pulses is reported. The transmittance for both pulse widths is fluence dependent. A five-level model of C60 is described that yields excellent agreement with both pulse-width data sets for incident fluences as high as approximately 1 J/cm2. Additional phenomena observed at higher fluences indicate that other mechanisms may be active and contribute to optical limiting in this regime. The application of C60 as an optical limiter material is discussed.

Optical limiting with C_60 in polymethyl methacrylate

We demonstrate optical limiting for the C(60) fullerene in polymethyl methacrylate (PMMA) as a solid polymer host. It is shown that the optical-limiting behavior is consistent with excited-state absorption (reverse saturable absorption) as a mechanism. We suggest that a higher threshold for optical limiting compared with that of C(60) in toluene is due to nonlinear scattering for the liquid. The performance of C(60) in PMMA is compared with that in chloroaluminum phthalocyanine, N-methylthioacridone, King's complex, and ruthenium King's complex in PMMA. Optical damage thresholds are reported.