Mechanisms of Electronic - Nuclear Energy Exchange in Molecular Rydberg States: A Time-Domain Study Focussed by Frequency-Domain Ideas

Massachusetts Institute Of Technology, Cambridge MA

Investigators

Abstract

Professor Robert Field of MIT is supported by the Experimental Physical Chemistry Program for a novel study of the dynamics of energy transfer in molecular Rydberg states. A nanosecond pulse will be used to prepare a carefully designed initial state, and a pair of scanned-delay phase-coherent IR femtosecond pulses will be used to study the dynamics of the initially localized excitation. In particular, the first pulse is used to prepare a coherent superposition among a well defined set of Rydberg states, and the second pulse interrogates the recurrences or rephasing. Detection will be by a field ionization voltage ramp. The mechanistic details of electronic and nuclear energy flow will be studied, varying the extent of resonance between interacting states. Alkaline earth monohalides such as CaF, CaCl and BaF prepared in molecular beams, previously studied by the PI in the frequency domain, will be utilized as model systems. The study of Rydberg states enhances our understanding of energy flow and storage in small molecules. As the method is improved, it may be applied to increasingly complicated molecules, with potential impacts on fields such as photochemistry and quantum information storage.