Chemists Report New Isotope Of Fluorine

New research from the Washington University in St. Louis has reported the first findings of a new form of fluorine, the isotope ¹³F. They found this as part of an experiment conducted at the National Superconducting Cyclotron Laboratory at Michigan State University (MSU).

We all know the chemical reactivity of fluorine, which is pretty high. The only stable isotope of fluorine is ¹⁹F. The newly found isotope ¹³F is four neutrons removed from the proton drip line, the boundary that delimits the zone beyond which atomic nuclei decay by the emission of a proton.

Robert J. Charity, research professor of chemistry, and Lee G. Sobotka, professor of chemistry and of physics, worked in collaboration with groups from MSU, Western Michigan University and University of Connecticut to make this discovery.

Charity said that although the lifetimes are extremely short for such nuclei, which have large excesses of neutrons or protons, studying them is of great interest in understanding the synthesis of elements.

The isotope ¹³F is the fifth new isotope that Charity and Sobotka have discovered together.

It is to be noted that all the new isotopes are very proton-rich and unstable to the emission of protons. The highest-energy protons inside these isotopes can tunnel through the Coulomb barrier and escape.

While the initial purpose of the experiment was to make a new isotope of oxygen, named “featherweight oxygen“. They created the new isotope of fluorine via a charge-exchange reaction with a beam of ¹³O. (A neutron in the ¹³O is removed and replaced by a proton.)

Charity explained that charge-exchange reactions like these have not typically been used for the creation of the very proton-rich isotopes in the past. He said that they were planning to find another new isotope using this reaction.

Journal Reference:
R. J. Charity, T. B. Webb, J. M. Elson, D. E. M. Hoff, C. D. Pruitt, L. G. Sobotka, K. W. Brown, G. Cerizza, J. Estee, W. G. Lynch, J. Manfredi, P. Morfouace, C. Santamaria, S. Sweany, C. Y. Tsang, M. B. Tsang, Y. Zhang, K. Zhu, S. A. Kuvin, D. McNeel, J. Smith, A. H. Wuosmaa, Z. Chajecki. Observation of the Exotic Isotope F13 Located Four Neutrons Beyond the Proton Drip Line. Physical Review Letters, 2021; 126 (13) DOI: 10.1103/PhysRevLett.126.132501

Press Release: Washington University in St. Louis