ESR Spectra of Alkali - PowerPoint Presentation

1. ESR Spectra of Alkali Metal Atoms on Helium Nanodroplets: a Theoretical Model for the Prediction of Helium Induced HFS ShiftsAndreas W. Hauser, Michael Filatov, and Wolfgang E. Ernst68th Int. Symp. on Molecular Spectroscopy, Columbus, Ohio June 17-21, 2013Institute of Experimental PhysicsResearch funded by Fonds zur Förderung der wissenschaftlichen Forschung & EU regional development fund (ERDF) Currently at UC BerkeleyMulliken CenterUniv. Bonn

2. 68th Int. Symp. on Molecular Spectroscopy, Columbus, Ohio June 17-21, 2013The hyperfine structure of alkali metal atomsSpecial case: single electron in s-orbital LiNaKRb

3. 68th Int. Symp. on Molecular Spectroscopy, Columbus, Ohio June 17-21, 2013ESR shifts induced by He-dropletsFree RbRb on He8000E =Experiment by M. Koch, G. Auböck, C. Callegari and W.E. Ernst, PRL 103, 035302 (2009) HFS constant

4. 68th Int. Symp. on Molecular Spectroscopy, Columbus, Ohio June 17-21, 2013HFS shifts induced by He-droplets?

5. 68th Int. Symp. on Molecular Spectroscopy, Columbus, Ohio June 17-21, 2013The strategy ….1) Basis set selection for atomic HFS (Ak=Li, Na, K, Rb)2) Calculation of the 2Σ1/2 ground states of Ak-He3) A DFT simulation of Ak attached to He-droplets4) Combine 2 and 3 to predict HFS of Ak on droplets

6. 68th Int. Symp. on Molecular Spectroscopy, Columbus, Ohio June 17-21, 20131) Choice of basis set

7. 68th Int. Symp. on Molecular Spectroscopy, Columbus, Ohio June 17-21, 20131) Choice of basis setLi:Na:K:Rb:* Young, D. : Computational Chemistry. New York : John Wiley and Sons, 2001*Note the huge contraction

8. 68th Int. Symp. on Molecular Spectroscopy, Columbus, Ohio June 17-21, 20131) Choice of basis setIsotropic hfs constants [MHz] in the atomic ground state:

9. 68th Int. Symp. on Molecular Spectroscopy, Columbus, Ohio June 17-21, 20132) HFS splitting in Ak-He diatomicPES of the ground stateRelative HFS shiftFor the diatomic systems: use the normalized elimination of the small component (NESC) method (Dyall, Filatov & Co., 1997-2011) in connection with the coupled-cluster singles and doubles (CCSD) formalism.

10. 68th Int. Symp. on Molecular Spectroscopy, Columbus, Ohio June 17-21, 20133) DFT calculationsRb

11. 68th Int. Symp. on Molecular Spectroscopy, Columbus, Ohio June 17-21, 20133) DFT calculationsHe-droplet with N = 500* figure from J. Poms, A.W. Hauser and W.E. Ernst, PhysChemChemPhys 14, 1558 (2012)

12. 68th Int. Symp. on Molecular Spectroscopy, Columbus, Ohio June 17-21, 20133) DFT calculations: Energy

13. 68th Int. Symp. on Molecular Spectroscopy, Columbus, Ohio June 17-21, 20133) DFT calculations: DensityHe-droplet with N = 500* figure from J. Poms, A.W. Hauser and W.E. Ernst, PhysChemChemPhys 14, 1558 (2012)

14. 68th Int. Symp. on Molecular Spectroscopy, Columbus, Ohio June 17-21, 2013Relevant areaAk-HeN with: blue  N = 50, red  N = 100, green  N = 200, magenta  N = 500

15. 68th Int. Symp. on Molecular Spectroscopy, Columbus, Ohio June 17-21, 20134) Putting things together...

16. 68th Int. Symp. on Molecular Spectroscopy, Columbus, Ohio June 17-21, 20134) Putting things together... +From He-DFT codeFrom NESC/CCSD calculationwith r0 denoting the position ofalkali-metal atom.

17. 68th Int. Symp. on Molecular Spectroscopy, Columbus, Ohio June 17-21, 20134) Putting things together... See also A. W. Hauser, T. Gruber, M. Filatov, and W. E. Ernst, ChemPhysChem 14, 716 (2013)

18. 68th Int. Symp. on Molecular Spectroscopy, Columbus, Ohio June 17-21, 2013SummaryHelium droplet environment affects ESR spectra of alkali-metal atomsEffect is mainly related to isotropic HFS constant → s-orbital compression? 'Dimer' picture: Generalization from Ak-He diatomic to Ak on He dropletExperimental data for Rb can be reproduced; Li, Na, and K predicted

19. 68th Int. Symp. on Molecular Spectroscopy, Columbus, Ohio June 17-21, 2013Acknowledgments to:Austrian Science Fundgrant P19759-N20 European CommissionERDF programme ERDF

20. 68th Int. Symp. on Molecular Spectroscopy, Columbus, Ohio June 17-21, 2013Graz, 18th - 22nd August 2014XXIInd International Symposium on the Jahn-Teller EffectInstitute of Experimental Physics

21. 68th Int. Symp. on Molecular Spectroscopy, Columbus, Ohio June 17-21, 2013Thank you for your attention !

22. 68th Int. Symp. on Molecular Spectroscopy, Columbus, Ohio June 17-21, 2013Markus Koch, Gerald Auböck, Carlo Callegari, and Wolfgang E. Ernst, Coherent Spin Manipulation and ESR on Superfluid Helium Nanodroplets, Phys. Rev. Lett. 103, 035302-1-4 (2009), also July 27, 2009 issue of Virtual Journal of Nanoscale Science & Technology, http://www.vjnano.org .Markus Koch, Johannes Lanzersdorfer, Carlo Callegari, John S. Muenter, and Wolfgang E. Ernst, Molecular beam magnetic resonance in doped helium nanodroplets: A setup for optically-detected ESR/NMR in the presence of unresolved Zeeman splittings, J. Phys. Chem. A 113, 13347-13356 (2009) (Festschrift in honor of Robert W. Field).Markus Koch, Carlo Callegari, and Wolfgang E. Ernst, Alkali-metal electron spin density shift induced by a helium nanodroplet, Mol. Phys. 108 (7), 1005-1011 (2010) (invited article in honour of Richard N. Zare). Alexander Volk, Johannes Poms, Markus Koch, and Wolfgang E. Ernst, 87Rb Electron Spin Resonance on Helium Nanodroplets: the Influence of Optical Pumping, J. Phys. Chem. A 115, 7065-70 (2011)(Festschrift in honor of J. Peter Toennies).References:ESR experiments:

23. 68th Int. Symp. on Molecular Spectroscopy, Columbus, Ohio June 17-21, 2013References:DFT code:

24. 68th Int. Symp. on Molecular Spectroscopy, Columbus, Ohio June 17-21, 2013References:Relativistic theory:

25. 68th Int. Symp. on Molecular Spectroscopy, Columbus, Ohio June 17-21, 2013References:Basis sets:

26. 68th Int. Symp. on Molecular Spectroscopy, Columbus, Ohio June 17-21, 2013References:Method used:

27. 68th Int. Symp. on Molecular Spectroscopy, Columbus, Ohio June 17-21, 2013