Physics Solid State Seminar: "From supra molecular chemistry at the spatial limits to spin

Sept. 24, 2008, Solid State Seminar [CM]
Dr. Paolo Messina, Argonne National Lab
"From supra molecular chemistry at the spatial limits to spin
noise in single molecules"
Abstract:  Supramolecular chemistry took inspiration from the
design principles of biological systems. The rational design of
several molecular assemblies by the exploitations of a combination
of non covalent interaction is at the heart of this exciting field.
Surprisingly the same design concepts and principles still holds at
the nanometer scale in a 2D constrained scenario1. In particular
the exploitation of coordinative bonding at surface can generate
chiral complexes and lead to the fabrication of 1D nanometer scale
helicates and chiral 2D nanometer scales arrays2-4.
But one question arises: How can these molecules be spectroscopic
investigated at the nanometer scale? Is there a possibility to
investigate them with local magnetic resonances?
In an attempt to answer this question we have designed a number
of different paramagnetic molecular nanostructures at the solid
air interface5, 6 and measured their ESR and ENDOR spectra at the
surface (ESR). These samples will eventually serve as a base for
single molecular Electron spin spectroscopy.  At the same time we
have started the investigation of spin noise as possible tool to
measure the spin dynamics of individual molecules supported on a
surface7. The detection of spin noise in small ensemble is one
possible root for detecting spin dynamics form assemblies of a
few molecules down to 1. Recent results8 will also be discussed in
the framework of the above.  The talk will conclude with an open
question " is single nuclear spin  detachable and can NMR be extended
to nanoscopic systems?9, 10"


1. Barth, J. V.; Costantini, G.; Kern, K., Engineering atomic
and molecular nanostructures at surfaces. Nature 2005, 437, (7059), 671-679.
2. Messina, P., Metal-Organic Fabrication of 1D and 2D Coordination
Networks at Cu(100) in preparation 2008.
3. Messina, P.; Dmitriev, A.; Lin, N.; Spillmann, H.; Abel, M.;
Barth, J. V.; Kern, K., Direct observation of chiral metal-organic
complexes assembled on a Cu(100) surface. Journal of the American
Chemical Society 2002, 124, (47), 14000-14001.
4. Spillmann, H.; Dmitriev, A.; Lin, N.; Messina, P.; Barth, J. V.;
Kern, K., Hierarchical assembly of two-dimensional homochiral nanocavity
arrays. Journal of the American Chemical Society 2003, 125, (35), 10725-10728.
5. Messina, P.; Fradin, F., Imaging Single Spin Probes Embedded in
a conductive Diamagnetic Layer. 2008, submitted for review.
6. Mannini, M.; Sorace, L.; Gorini, L.; Piras, F. M.; Caneschi, A.;
Magnani, A.; Menichetti, S.; Gatteschi, D., Self-assembled organic
radicals on Au(111) surfaces: A combined ToF-SIMS, STM, and ESR study.
Langmuir 2007, 23, (5), 2389-2397.
7. Messina, P.; Mannini, M.; Caneschi, A.; Gatteschi, D.; Sorace, L.;
Sigalotti, P.; Sandrin, C.; Prato, S.; Pittana, P.; Manassen, Y.,
Spin noise fluctuations from paramagnetic molecular adsorbates on surfaces.
Journal of Applied Physics 2007, 101, (5), 053916.
8. Komeda, T.; Manassen, Y., Distribution of frequencies of a
single precessing spin detected by ESR-STM. Applied Physics Letters 2008,
92, 212506.
9. Meriles, C. A., Optical detection of NMR in organic fluids.
Concepts in Magnetic Resonance Part A 2008, 32A, (2), 79-87.
10. Taylor J.M., C. P., Childress L., Jang L., Budker D. , High
Sensitivity diamond magnetometer with nanoscale resolution. Nature
Physics 2008, accepeted for publication