Date of Thesis
Spring 2026
Description
Iron oxide nanoparticles (IONPs) are a specific type of nanoparticle made from a cluster of iron and oxygen atoms surrounded by a protective coat of organic surfactant, typically oleic or stearic acid. These nanoparticles are commonly produced by thermal decomposition of small starting molecules, called precursor complexes. Iron oxide nanoparticles are of great significance in materials science and medicine because of their unique size-dependent magnetic properties. The purpose of this research is to understand how these molecular precursors assemble and transform before nanoparticle formation occurs. Previous studies have shown that the choice and makeup of the precursor strongly influence the size, shape, and properties of the final nanoparticles, highlighting the importance of understanding precursor behavior on its own. This work presents an investigation of IONP precursor complexes through the development of a simplified model system where the organic surfactant (oleate or stearate) has been replaced by 4,4,4-trifluorobutyrate (TFB). The introduction of fluorine via TFB allows structural changes in the precursor complexes to be tracked at the molecular level using fluorine-19 nuclear magnetic resonance (19F-NMR) spectroscopy, a sensitive and minimally invasive technique, that is capable of characterizing paramagnetic iron complexes. This study demonstrates the structural heterogeneity of iron-TFB complexes by identifying a complex distribution of cluster sizes, primarily containing three or eleven iron atoms. The relative ratios of these products are governed by the stoichiometric relation between iron, TFB, and added base, highlighting a level of structural complexity previously unrecognized in the field.
Keywords
Paramagnetic Iron Complexes, fluorine-19 NMR, IONPs, Precursor systems
Access Type
Honors Thesis
Degree Type
Bachelor of Science
Major
Chemistry
Minor, Emphasis, or Concentration
Philosophy
First Advisor
Will Kerber
Second Advisor
Robert Stockland
Third Advisor
Angela Wu
Recommended Citation
Sahni, Sanoosha, "Modeling Iron Oxide Nanoparticle Precursors: Growth of an Undecanuclear Iron(III) Cluster" (2026). Honors Theses. 769.
https://digitalcommons.bucknell.edu/honors_theses/769