On the most fundamental level, through the molecular origins of life and photosynthesis, the interaction of light with matter has played an essential role. The many applications of these interactions continue to revolutionize society through advances in medicine, communications, technology, and entertainment. Controlling the fundamental way in which matter interacts with light represents a major priority for many phenomena of great importance for society. This grand challenge is yet to be fully conquered despite the efforts of many chemists and physicists. With this award, the Chemical Structure, Dynamics and Mechanisms-B Program of the Division of Chemistry is supporting Professor Carlos E. Crespo-Hernández of Case Western Reserve University to investigate whether strategic structural modification of the DNA component pyrimidine can be used to rationally control the dissipation of energy, processes critical to DNA photochemistry and photostability. Prof. Crespo-Hernández and his research students use a combination of experiment and theory to examine this innovative idea. The transformative potential of this research is the development of molecular design principles for the control of light-induced pathways in biological and other organic molecules in general. Prof. Crespo-Hernández seeks to motivate students to enter and persist in scientific studies and careers by providing research opportunities to high school, undergraduate and graduate students, and by mentoring and serving as a role model. The interests of these students are heightened by opportunities for cross- and multidisciplinary research and training in important areas of modern photochemistry and photobiology, time-resolved techniques, and computational methods, and by exposure to national and international collaborations. Research opportunities are provided for economically disadvantaged and underrepresented students from the Greater Cleveland area.
In this research, Professor Crespo-Hernández is investigating whether selective functionalization of the pyrimidine chromophore can be used to rationally control the radiative and nonradiative decay pathways that are critical to nucleic acid photochemistry. Prof. Crespo-Hernández and his research students examine this innovative idea by gathering experimental and theoretical data using femto-to-microsecond transient absorption spectroscopy and multiconfigurational calculations. The objectives include: 1) unravel the electronic relaxation pathways in rationally selected nucleic acid derivatives; 2) map the topology of the potential energy surfaces; and 3) establish structure-dynamics relationships to reveal how functionalization regulates radiative and nonradiative decay pathways. Close collaboration with the theoretical group of Professor Inés Corral of the Universidad Autónoma de Madrid, Spain enhance the impact and increase fundamental understanding of the transformative science proposed. Understanding how functionalization of the pyrimidine chromophore regulates the electronic relaxation pathways in nucleic acid derivatives can assist in the development of therapeutic drugs, crosslinking agents, and fluorescent biomarkers, and may hold the key for understanding why the genetic alphabet is composed of only four nucleobases.
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.
