Uncovering the Secret Life of Molecules: Adventures in ... · Uncovering the Secret Life of...

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Uncovering the Secret Uncovering the Secret Life of Molecules: Life of Molecules:

Adventures in Physics Adventures in Physics and Chemistryand Chemistry

‘Picture’ of an atom

Molecules: Water

Electron density around the Oxygen atom is 10x that around the Hydrogen atoms

Dimer (2 water molecules)

Hydrogen bond

Structure of Ice: Solid water(more is different!)

Laser lab in Amsterdam

Absorption Spectrum of Liquid Water

The Horse in Motion: The Horse in Motion: MuybridgeMuybridge 18781878

Water Molecule Vibrations

Femtosecond lasers

15 fs

H+

Intermolecular Proton Transfer

Diffraction Patterns: Learning about the arrangement of atoms

Making Movies of Molecules with Making Movies of Molecules with UltrafastUltrafast Electron DiffractionElectron Diffraction

UED is a stroboscopic technique that can determine the ‘instantaneous’ atomic configuration of molecules and materials

during photoinduced processes

Ultrafast (t<10-10 s) diffractometer

Lattice temperature rises (vibrational excitation)

Homogeneous nucleation of melt zones – structral collapse

Liquid-like disordered state is reached

An atomic level An atomic level view of meltingview of melting

TimeTime--Resolved (150 Resolved (150 psps) X) X--ray ray Crystallography at the ESRFCrystallography at the ESRF

F. Schotte, M. H. Lim, T. A. Jackson, A. V. Smirov, J. Soman, J. S. Olson, G. N. Phillips, M. Wulff, P. A. Anfinrud, Science 300 (2003) 1944.

Watching a Protein as it FunctionsWatching a Protein as it FunctionsF. Schotte, M. H. Lim, T. A. Jackson, A. V. Smirov, J. Soman, J. S. Olson, G. N.

Phillips, M. Wulff, P. A. Anfinrud, Science 300 (2003) 1944.