LEAPS-MPS: Developing a Spectroscopic Map for Terminal Alkynes

Haverford College, Haverford PA

Investigators

Abstract

This award is funded in whole or in part under the American Rescue Plan Act of 2021 (Public Law 117-2). Raman spectroscopy is an important tool for the investigation of a diverse array of molecular systems. Effective use of this tool requires a clear and deep understanding of the vibrations within molecules that are associated with the absorption of light with specific amounts of energy. Alkynes, molecules with carbon-carbon triple bonds, have recently been used in Raman spectroscopy to understand the structure and dynamics of proteins that cells use to make new molecules. This new use of alkynes highlights the need to more deeply understand alkyne vibrations and thus their Raman spectroscopic signals. In this project, funded by the Mathematical and Physical Sciences Directorate and housed in the Chemistry Division, Professor Clyde Daly and his students at Haverford College will develop relationships called “spectroscopic maps” between the Raman absorption of alkyne molecules and their molecular environments. These maps can be used in molecular simulations to better understand how cells make new molecules, relevant to the design of new drugs and materials. This project will also advance computational and experimental uses of Raman spectroscopy. The methods developed during this project will be used to build educational materials for advanced and first year courses related to vibrational spectroscopy. Engagement in the research of students from backgrounds underrepresented in Mathematical and Physical Sciences fields will be prioritized through avenues such as payment for work-study (disproportionately low-income or first-generation college students) and recruitment of students from disadvantaged backgrounds. This project will engage undergraduate students in the development of a vibrational spectroscopic map for terminal alkyne containing molecules at Haverford College. The carbon-carbon triple bond stretching vibration of terminal alkynes has been increasingly used as a Raman vibrational probe to understand proteins, other biological molecules, and materials. A spectroscopic map will enable the calculation of Raman spectra from molecular dynamics simulations. The process of building the spectroscopic map will also uncover the reasons for the substantial Raman frequency shift of the vibration of interest between different solvation environments. The aims for this project are threefold: (1) create a spectroscopic map that is appropriate for answering biophysical questions related to the acyl carrier protein relevant to our collaborators; (2) advance the paradigm of spectroscopic map design to include machine learning more fully as a tool and universality as a goal; (3) understand the factors that lead to Raman frequency shifts in terminal alkynes. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.