New molecular complexes of fullerenes C60 and C70 with tetraphenylporphyrins [M(tpp)] in which M-H2, MnII, CoII, CuII, ZnII and Fe(III)Cl, have been synthesised. Crystal structures of two C60 complexes with H2TPP, which differ only in the number of benzene solvated molecules, and C60 and C70 complexes with [Cu(tpp)] have been studied. The fullerene molecules form a honeycomb motif in H2TPP.2C60. 3C6H6, puckered graphite-like layers in H2TPP.2C60.4C6H6, zigzag chains in [Cu(tpp)].C70.1.5C7H8.0.5C2HCl3 and columns in [Cu(tpp)]2.C60. H2TPP has van der Waals contacts with C60 through nitrogen atoms and phenyl groups. Copper atoms of the [Cu(tpp)] molecules are weakly coordinated with C70, but form no shortened contacts with C60. The formation of molecular complexes with fullerenes affects the ESR spectra of [M(tpp)] (M = Mn, Co and Cu). [Mn(tpp)] in the complex with C70 lowers its spin state from S = 5/2 to S = 1/2, whereas [Co(tpp)] and [Cu(tpp)] change the constants of hyperfine interaction. ESR, IR, UV-visible and X-ray photoelectron spectroscopic data show no noticeable charge transfer from the porphyrinate to the fullerene molecules.
The suggested approach "Selected set of samples + selected set of analytical tools" occurred quite efficient when applying to sp 2 amorphous carbons, thus providing a transformation of 'amorphous' representation of the issue, based on particulars, into a 'crystalline' one based on a limited set of fixed commonalities. The slogan first part implies a set of different-origin solid samples. The second part concerns analytical tools, the most suitable to achieve the goal. The parts combining means the application of each tool to the whole set of samples. In the current study, two natural sp 2 amorphous carbons, namely, shungite carbon and antraxolite, as well as two engineered products -carbon blacks CB632 and CB624, all of the four bodies belonging to the elitist highest-carbon-content sp 2 species, were subjected to analytical study by using modern structural and compositional analytical techniques. The approach has allowed disclosing the following steady points that are common to the whole class of this carbon allotrope and that may lay the foundation of consolidate, more 'crystalline' representation of what are sp 2 amorphous carbons:1. sp 2 Amorphous carbons are products of particular chemical reactions related to their basic structural units. Further macroscopic agglomeration of the latter plays a subsidiary role. 2. The units represent framed graphene molecules of 1-2 nm and 1-x*10 (x=1-3) nm in size in the case of natural and engineered products, respectively.3. Framing of graphene molecules, predominantly incomplete with respect to the number of vacant places, concerns only edge atoms and is implemented by the related chemical additives, such as hydrogen, oxygen, nitrogen, sulfur and halogens which are attached to the carbon core via chemical bonding. 4. The molecules small size provides a countable number of newly formed chemical bonds.INS and XPS allow attributing the bonds to chemical compositions restricted by number while QCh ensures reliable support. 5. Temperature and pressure as well as physical state and chemical content of surrounding media are the main factors governing geochemistry and technical chemistry of carbon products. 6. Graphene molecules, laying the foundation of sp 2 amorphous carbons, are strongly radicalized due to which the latter acquire a new facet in the space of their properties, being the largest repository of stable radicals.
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