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Electrodynamical forbiddance of a strong quadrupole light-molecule interaction in fullerene C60 and its withdrawal in fullerene C70

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 نشر من قبل Aleksey Polubotko
 تاريخ النشر 2017
  مجال البحث فيزياء
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It is demonstrated that in fullerene C70 which can be considered as a deformed fullerene C60 in some sense there is a withdrawal of an electrodynamical forbiddance of a strong quadrupole light-molecule interaction which is realized in the fullerene C60. This situation occurs because of the reduction of symmetry of C60 from the icosahedral symmetry group Yh to the group D5h. The withdrawal results in appearance of the lines in the SERS spectra of C70 which are forbidden in usual Raman scattering and are allowed in infrared absorption while such lines are forbidden in the SERS spectrum of the fullerene C60 due to the electrodynamical forbiddance. The measured SERS spectra of C70 demonstrates existence of such lines that strongly confirms our ideas about the dipole quadrupole SERS mechanism.



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It is demonstrated that the forbidden lines, which must be present in the SERS, TERS and SEIRA spectra of molecules with sufficiently high symmetry, associated with a strong quadrupole light-molecule interaction, are absent in the fullerene C60. This result is an experimental manifestation of an electrodynamical forbiddance of the strong quadrupole light-molecule interaction, which must be not only in molecules with cubic symmetry groups, but in the fullerene C60 also.
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