Poster Presentation 2014 International Biophysics Congress

Nuclear magneto-optic spectroscopy (#675)

Juha Vaara 1 , Li-juan Fu 1
  1. University of Oulu, Oulu, Finland

Optical detection of nuclear magnetization could provide improved sensitivity in site-specific  spectroscopy and resolution in imaging of biomolecular systems. The discovery of nuclear spin optical rotation1 (NSOR), Faraday effect due to nuclear magnetization, marked the beginning of nuclear magneto-optic spectroscopy (NMOS). Later, optical shift between different molecular liquids has been detected2 (after theoretical prediction3) and alternative set-ups for enhanced measurements have been presented4 5. In theoretical phenomenology, means of obtaining high-resolution signals have been proposed3, and medium6 and heavy-atom7 effects investigated.

Also other phenomena lend themselves to NMOS. In Cotton-Mouton effects, ellipticity is induced to linearly polarized light due to interactions with nuclear quadrupole8, spin and an external magnetic field9, and two spins10 in the Voigt set-up, perpendicular to the optical beam. Here, partial orientation of the molecules arises, dependent on dynamic polarizability and the NMR quadrupole coupling, shielding, and spin-spin coupling, respectively. A promising method concerns spin-induced circular dichroism11, due to differential absorption of the left- and right-circularly polarized light. Finally, chiral recognition is proposed due to spin-induced magnetochiral birefringence12.

  1. I. M. Savukov, S.-K. Lee, and M. V. Romalis, Nature, 442, 1021 (2006).
  2. J. Shi, S. Ikäläinen, J. Vaara, and M. V. Romalis, J. Phys. Chem. Lett., 4, 437 (2013).
  3. S. Ikäläinen, P. Lantto, M. V. Romalis, and J. Vaara, Phys. Rev. Lett., 105, 153001 (2010).
  4. D. Pagliero and C. A. Meriles, Proc. Nat. Acad. Sci. (USA), 208, 19510 (2011).
  5. I. M. Savukov, H.-Y. Chen, T. Karaulanov, and C. Hilty, J. Magn. Reson., 232, 31 (2013).
  6. T. S. Pennanen, S. Ikäläinen, P. Lantto, and J. Vaara, J. Chem. Phys., 136, 184502 (2012).
  7. S. Ikäläinen, P. Lantto, and J. Vaara, J. Chem. Theory Comput., 8, 91 (2012).
  8. L.-j. Fu and J. Vaara, J. Chem. Phys., 140, 024103 (2014).
  9. L.-j. Fu and J. Vaara, ChemPhysChem, in press (2014).
  10. L.-j. Fu and J. Vaara, J. Chem. Phys., 138, 204110 (2013).
  11. J. Vaara, A. Rizzo, J. Kauczor, P. Norman, and S. Coriani, J. Chem. Phys., 140, 134103 (2014).
  12. L.-j. Fu, J. Cukras, S. Coriani, and J. Vaara, in preparation.