3000 Broadway, New York, NY 10027
We study equilibrium and dynamical properties of molecules at interfaces. Many important chemical processes occur at liquid interfaces. Examples include cell membranes which host a variety of vital reactions in biology and life science, air/water interface (environmental importance), solid/liquid and liquid/liquid interfaces in catalysis and electrochemistry, surfaces of self-organized structures such as phospholipid bilayers, liposomes, and micelles, and surfaces of colloids and nanoparticles.
Experiments performed in our lab are a unique combination of ultrafast (femtosecond) and surface-selective capabilities.
We use nonlinear optical spectroscopies to selectively probe molecules in the the very thin interfacial region (~10 Å). The second order nonlinear optical processes of Second Harmonic Generation (SHG) and Sum Frequency Generation (SFG) are symmetry-forbidden in bulk media, but allowed at interfaces.
In our experiments we use femtosecond lasers to perform ultrafast time-resolved measurements. This allows to observe motions and reactions of molecules at interfaces in real time. Our current time resolution is ~100 fs.
Here are examples of static molecular properties at liquid interfaces that have been characterized in our group:
* pK of acids and bases
* Orientation of adsorbed molecules
* Electronic spectra
* Surface potential of charged interfaces
* Surface properties of microscopic particles: metal nanoparticles, liposomes, semiconductor quantum dots, clays, polymer beads, emulsions
* Biomembrane surfaces
Dynamical molecular processes at interfaces include
* Intermolecular energy transfer
* Orientational relaxation
* Solvation dynamics
Prof. Kenneth B. Eisenthal ( email@example.com )
Dr. Yi Rao, research scientist (firstname.lastname@example.org )
Dr. Louis Haber, post-doc scientist (email@example.com)
Sung Young Hong, graduate student (firstname.lastname@example.org)
Sheldon Kwok, undergraduate student (email@example.com)
Havermeyer Hall Offices: Room 604-605 Laser Labs: Room 603 Wet Lab: Room 610
Department of Chemistry, Columbia University, 3000 Broadway, New York, NY 10027
Phone: (212) 854-2094