Abstract by Aldair Alejandro

Personal Infomation

Presenter's Name

Aldair Alejandro

Degree Level



Brittany Knighton
Megan Nielson
Tanner Hardy
Lauren Rawlings
Jeremy Johnson
Eric Sevy

Abstract Infomation


Chemistry and Biochemistry

Faculty Advisor

Jeremy Johnson


Using High-field Terahertz Spectroscopy to Measure Anharmonicity and Collisional Energy Transfer in Mono-fluorobenzene


Ultrafast spectroscopy is a powerful tool that uses ultrashort pulse lasers to study properties of materials on extremely small (picosecond) time scales. We use high-field terahertz (THz) spectroscopy to strongly excite vibrations in solids. Atoms inside the crystals can be moved far from their equilibrium positions using strong THz pulses, which can let us observe coupling between vibrations due to the anharmonic potential energy surface. Computational and experimental work on molecular systems reveals that anharmonic modes are most efficient in transferring energy when molecules collide. In this work, we want to use intense THz pulses to excite atoms in molecules far from their equilibrium positions in the gas phase instead of the solid phase, to also be able to predict which molecular vibrational modes are anharmonic, and therefore more important to energy transfer. Mono-fluorobenzene will serve as a useful starting point to measure its anharmonicity and how it impacts collisional energy transfer.