Optical spectra of C ₆₀ and C ₇₀ complexes: their similarities and differences

Abstract

Some possible uses of vibrational and electronic spectroscopies in characterising the basic interactions in C60 and C70 complexes are pointed out. We report on the wealth of infrared spectra of (usually) single crystals of C60 and C70 clathrates and complexes with organic donors. The changes in the spectral parameters of the complexes in comparison with those of the neutral fullerene molecules are attributed to redistribution of the charge on the spherical C60 or elongated C70 molecules in their compounds. Some general considerations on the origin of the IR, NIR, VIS and UV spectral variations are also given. © 1998 John Wiley & Sons, Ltd.

Molecular State and Distribution of Fullerenes Entrapped in Sol−Gel Samples

“…C 70 also absorbs in this region, but its absorption maximum is shifted toward shorter wavelength (470 nm). As expected, these spectra agree well with those in the literature, 14,15,[30][31][32] and the presence of these bands, particularly the 400-, 600-, and 621-nm bands of C 60 , is a clear indication that the C 60 and C 70 molecules are in monomeric form. 14,15 Also shown in the figure is the spectrum of a solution containing a mixture of these two fullerenes at one-half concentration each (0.5 mg/mL C 60 and 0.05 mg/mL C 70 ).…”

Carbon nanomaterials in biological systems

“…Both C 60 and C 70 absorb strongly in the ultraviolet region, though C 70 has a higher absorption than C 60 in the visible regions, possibly due to its elongated form and reduced symmetry [52,53]. C 60 and C 70 are known to be soluble in organic solvents such as toluene or benzene which can be photoexcited to induce weak fluorescence from visible to near infrared [52][53][54][55][56]. Concomitantly we have recorded the fluorescence of C 70 -gallic acid in water which exhibited two distinct peaks at ∼540 and 719 nm, and attributed the former to well solubilized C 70 -gallic acid and the latter to large C 70 aggregates (figure 8(b)).…”

Морфологія Поверхні Плівок Суміші Фулеренів C60/С70. Ідентифікація C60 Та С70 У Плівках C60/С70 За Їх Спектрами Поглинання

“…Such a cluster is described by the point symmetry group 𝐼 ℎ . A molecular cluster C 70 has a quasi-ellipsoidal shape owing to additional 5 hexagonal faces along the equatorial line, and it is described by the point symmetry group 𝐷 5ℎ [2].…”

“…A review of the most important theoretical and experimental papers aimed at elucidating the properties of the lowest excited states in C 60 and C 70 was made in work [16]. The diagrams of the energy levels of the C 60 and C 70 molecules were given in works [2,14,[17][18][19][20][21].…”