2026/05/15 by Alan Hirales, Mounesha N. Garaga, Justin Nakamura +4 · 1 voice
Materials Science · Physics and Astronomy · #Boron and Carbon Nanomaterials Research #Rare-earth and actinide compounds #Superconductivity in MgB2 and Alloys
paper · doi:10.1021/acs.inorgchem.6c00188
openalex publication_date 2026/05/15 · openalex created_date 2026/05/16 · openalex updated_date 2026/06/15
We explore the effects of lithium doping on the structure of three alkaline-earth hexaborides─CaB 6, SrB 6, and BaB 6 . Lithium incorporation was characterized using inductively coupled plasma mass spectrometry and X-ray diffraction analyses, demonstrating a systematic expansion of the cubic Pm3̅m lattice with increasing lithium concentration. Scanning and transmission electron microscopy revealed that lithium doping induces distinct surface pitting and localized lattice distortions. Solid-state 7 Li nuclear magnetic resonance (NMR) spectroscopy provided deeper insight into the lithium coordination environments. One-dimensional NMR confirmed the ionic character of lithium and demonstrated the presence of minor side products, which were largely eliminated by acid treatment of the powders. Two-dimensional exchange spectroscopy NMR identified two distinct ionic lithium environments within the BaB 6 lattice. The absence of cross-peaks with side-product signals confirmed spatial separation and chemical stability of lattice-confined lithium. Our analyses establish a foundational understanding of alkali metal doping behavior in boron-rich ceramics and highlight the structural role of lithium as a dopant in hexaboride systems, supporting future investigations into how lithium incorporation may influence electronic properties.